2016 EQUITY INCENTIVE PLAN NOTICE OF RESTRICTED STOCK UNIT AWARD (EMPLOYEE)

Exhibit 10.6

2016 EQUITY INCENTIVE PLAN

NOTICE OF RESTRICTED STOCK UNIT AWARD

(EMPLOYEE)

Unless otherwise defined herein, the terms defined in the Cascadian Therapeutics, Inc. (the “Company”) 2016 Equity Incentive Plan (the “Plan”) will have the same meanings in this Notice of Restricted Stock Unit Award and the electronic representation of this Notice of Restricted Stock Unit Award established and maintained by the Company or a third party designated by Cascadian Therapeutics, Inc. (the “Notice”).

Name:

Address:

You (“Participant”) have been granted an award of Restricted Stock Units (“RSUs”) under the Plan subject to the terms and conditions of the Plan, this Notice and the attached Restricted Stock Unit Award Agreement (hereinafter the “Agreement”), including any applicable country-specific provisions in the appendix attached hereto (the “Appendix”), which constitutes part of this Agreement.

By accepting (whether in writing, electronically or otherwise) the RSUs, Participant acknowledges and agrees to the following:

Participant understands that Participant’s employment or consulting relationship or service with the Company or a Parent or Subsidiary is for an unspecified duration, can be terminated at any time (i.e., is at will), except where otherwise prohibited by applicable law and that nothing in this Notice, the Agreement or the Plan changes the nature of that relationship. Participant acknowledges that the vesting of the RSUs pursuant to this Notice is earned only by continuing Service as an Employee, Director or Consultant. Participant agrees and acknowledges that the Vesting Schedule may change prospectively in the event that Participant’s service status changes between full and part time status in accordance with Company policies relating to work schedules and vesting of awards. Participant also understands that this Notice is subject to the terms and conditions of both the Agreement and the Plan, both of which are incorporated herein by reference. Participant has read both the Agreement and the Plan. By accepting the RSUs, Participant consents to the electronic delivery as set forth in the Agreement.

CASCADIAN THERAPEUTICS, INC.

2016 EQUITY INCENTIVE PLAN

RESTRICTED STOCK UNIT AWARD AGREEMENT (EMPLOYEE)

Unless otherwise defined herein, the terms defined in the Cascadian Therapeutics, Inc. (the “Company”) 2016 Equity Incentive Plan (the “Plan”) will have the same defined meanings in this Restricted Stock Unit Award Agreement (the “Agreement”).

Participant has been granted Restricted Stock Units (“RSUs”) subject to the terms, restrictions and conditions of the Plan, the Notice of Restricted Stock Unit Award (the “Notice”) and this Agreement, including any applicable country-specific provisions in the appendix attached hereto (the “Appendix”), which constitutes part of this Agreement.

1. Vesting. Except as otherwise provided in this Agreement and subject to Section 2.6 of the Plan, the RSU shall vest in accordance with the vesting schedule in the Notice; provided that Participant has continuously been in Service to the Company from the Date of Grant through the vesting date. Notwithstanding the foregoing, the vesting schedule set forth in the Notice and this Section 1 of the Agreement will be subject to any vesting or vesting acceleration provisions that may be set forth in Participant’s employment agreement or other agreement with Company, or that may be approved by the Committee.

2. Settlement. Settlement of RSUs will be made within 30 days following the applicable Vesting Date. Settlement of RSUs will be in Shares. No fractional RSUs or rights for fractional Shares shall be created pursuant to this Agreement.

3. No Stockholder Rights. Unless and until such time as Shares are issued in settlement of vested RSUs, Participant will have no ownership of the Shares allocated to the RSUs and will have no rights to dividends or to vote such Shares.

4. Dividend Equivalents. Dividends, if any (whether in cash or Shares), will not be credited to Participant.

5. Non-Transferability of RSUs. The RSUs and any interest therein will not be sold, assigned, transferred, pledged, hypothecated, or otherwise disposed of in any manner other than by will or by the laws of descent or distribution or court order or unless otherwise permitted by the Committee on a case-by-case basis.

6. Termination.

(a) Termination. Except as may be set forth in any other employment, change in control, severance or similar agreement or policy between Participant and the Company, if Participant’s Service terminates for any reason, all unvested RSUs will be forfeited to the Company forthwith, and all rights of Participant to such unvested RSUs will immediately terminate without payment of any consideration to Participant.

(b) Termination from Service. For purposes of this Agreement, Participant’s Service will be considered terminated as of the date Participant is no longer providing Services (regardless of the reason for such termination and whether or not later found to be invalid or in breach of employment laws in the jurisdiction where Participant is employed or the terms of Participant’s employment agreement, if any) and will not, subject to the laws applicable to Participant’s Award, be extended by any notice period mandated under local laws (e.g., Service would not include a period of “garden leave” or similar period). Participant acknowledges and agrees that the Vesting Schedule may change prospectively in the event Participant’s Service status changes between full and part-time status and/or in the event Participant is on an approved leave of absence in accordance with Company policies relating to work schedules and vesting of awards or as determined by the Committee, as applicable. Unless otherwise provided in this

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Agreement or determined by the Committee, Participant acknowledges that, except as set forth in Section 6(b) or (c), the vesting of the Shares pursuant to this Notice and Agreement is earned only by continued Service. In case of any dispute as to whether termination of Service has occurred, the Committee will have sole discretion to determine whether such termination of Service has occurred and the effective date of such termination (including whether Participant may still be considered to be providing Services while on an approved leave of absence).

7. Withholding Taxes. Participant acknowledges that, regardless of any action taken by the Company or, if different, Participant’s employer (the “Employer”) the ultimate liability for all income tax, social insurance, payroll tax, fringe benefits tax, payment on account or other tax-related items related to Participant’s participation in the Plan and legally applicable to Participant (“Tax-Related Items”), is and remains Participant’s responsibility and may exceed the amount actually withheld by the Company or the Employer. Participant further acknowledges that the Company and/or the Employer (1) make no representations or undertakings regarding the treatment of any Tax-Related Items in connection with any aspect of the RSUs, including, but not limited to, the grant, vesting or settlement of the RSUs and the subsequent sale of Shares acquired pursuant to such settlement and the receipt of any dividends; and (2) do not commit to and are under no obligation to structure the terms of the grant or any aspect of the RSUs to reduce or eliminate Participant’s liability for Tax-Related Items or achieve any particular tax result. Further, if Participant is subject to Tax-Related Items in more than one jurisdiction between the date of grant and the date of any relevant taxable or tax withholding event, as applicable, Participant acknowledges that the Company and/or the Employer (or former employer, as applicable) may be required to withhold or account for Tax-Related Items in more than one jurisdiction.

Prior to any relevant taxable or tax withholding event, as applicable, Participant agrees to make adequate arrangements satisfactory to the Company and/or the Employer to satisfy all Tax-Related Items. In this regard, Participant authorizes the Company and/or the Employer, or their respective agents, at their discretion, to satisfy the obligations with regard to all Tax-Related Items by one or a combination of the following:

all under such rules as may be established by the Committee and in compliance with the Company’s Insider Trading Policy, if applicable; provided however, that if Participant is a Section 16 officer of the Company under the Exchange Act, then the Committee (as constituted in accordance with Rule 16b-3 under the Exchange Act) shall establish the method of withholding from alternatives (i)-(v) above, and the Committee shall establish the method prior to the Tax-Related Items withholding event. Depending on the withholding method, the Company may withhold or account for Tax-Related Items by considering applicable minimum statutory withholding amounts or other applicable withholding rates, including maximum applicable rates, in which case Participant will receive a refund of any over-withheld amount in cash and will have no entitlement to the Common Stock equivalent. If the obligation for Tax-Related Items is satisfied by withholding in Shares, for tax purposes, Participant is deemed to have been issued the full number of Shares subject to the vested RSUs, notwithstanding that a number of the

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Shares are held back solely for the purpose of paying the Tax-Related Items. The Fair Market Value of these Shares, determined as of the effective date when taxes otherwise would have been withheld in cash, will be applied as a credit against the Tax-Related Items withholding.

Finally, Participant agrees to pay to the Company or the Employer any amount of Tax-Related Items that the Company or the Employer may be required to withhold or account for as a result of Participant’s participation in the Plan that cannot be satisfied by the means previously described. The Company may refuse to issue or deliver the Shares or the proceeds of the sale of Shares, if Participant fails to comply with Participant’s obligations in connection with the Tax-Related Items.

8. Nature of Grant. By accepting the RSUs, Participant acknowledges, understands and agrees that:

(a) the Plan is established voluntarily by the Company, it is discretionary in nature and it may be modified, amended, suspended or terminated by the Company at any time, to the extent permitted by the Plan;

(b) the grant of the RSUs is voluntary and occasional and does not create any contractual or other right to receive future grants of RSUs, or benefits in lieu of RSUs, even if RSUs have been granted in the past;

(c) all decisions with respect to future RSU or other grants, if any, will be at the sole discretion of the Company;

(d) the RSU grant and Participant’s participation in the Plan will not create a right to employment or be interpreted as forming an employment or services contract with the Company, the Employer or any Parent or Subsidiary;

(e) Participant is voluntarily participating in the Plan;

(f) the RSUs and the Shares subject to the RSUs are not intended to replace any pension rights or compensation;

(g) the RSUs and the Shares subject to the RSUs, and the income and value of same, are not part of normal or expected compensation for purposes of calculating any severance, resignation, termination, redundancy, dismissal, end-of-service payments, bonuses, long-service awards, pension or retirement or welfare benefits or similar payments;

(h) the future value of the underlying Shares is unknown, indeterminable and cannot be predicted with certainty;

(i) no claim or entitlement to compensation or damages will arise from forfeiture of the RSUs resulting from Participant’s termination of Service, and in consideration of the grant of the RSUs to which Participant is otherwise not entitled, Participant irrevocably agrees never to institute any claim against the Company, or any Parent or Subsidiary or the Employer, waives his or her ability, if any, to bring any such claim, and releases the Company, any Parent or Subsidiary and the Employer from any such claim; if, notwithstanding the foregoing, any such claim is allowed by a court of competent jurisdiction, then, by participating in the Plan, Participant will be deemed irrevocably to have agreed not to pursue such claim and agrees to execute any and all documents necessary to request dismissal or withdrawal of such claim;

(j) unless otherwise provided in the Plan or by the Company in its discretion, the RSUs and the benefits evidenced by this Agreement do not create any entitlement to have the RSUs or any such benefits transferred to, or assumed by, another company nor to be exchanged, cashed out or substituted for, in connection with any Corporate Transaction affecting the Shares; and

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(k) the following provisions apply only if Participant is providing services outside the United States:

9. No Advice Regarding Grant. The Company is not providing any tax, legal or financial advice, nor is the Company making any recommendations regarding Participant’s participation in the Plan, or Participant’s acquisition or sale of the underlying Shares. Participant is hereby advised to consult with his or her own personal tax, legal and financial advisors regarding his or her participation in the Plan before taking any action related to the Plan.

10. Data Privacy. Participant hereby explicitly and unambiguously consents to the collection, use and transfer, in electronic or other form, of Participant’s personal data as described in this Agreement and any other RSU grant materials by and among, as applicable, the Employer, the Company and any Parent or Subsidiary for the exclusive purpose of implementing, administering and managing Participant’s participation in the Plan.

Participant understands that the Company and the Employer may hold certain personal information about Participant, including, but not limited to, Participant’s name, home address and telephone number, date of birth, social insurance number or other identification number, salary, nationality, job title, any shares of stock or directorships held in the Company, details of all RSUs or any other entitlement to shares of stock awarded, canceled, exercised, vested, unvested or outstanding in Participant’s favor (“Data”), for the exclusive purpose of implementing, administering and managing the Plan.

Participant understands that Data will be transferred to the stock plan service provider as may be designated by the Company from time to time or its affiliates or such other stock plan service provider as may be selected by the Company in the future, which is assisting the Company with the implementation, administration and management of the Plan. Participant understands that the recipients of the Data may be located in the United States or elsewhere, and that the recipient’s country (e.g., the United States) may have different data privacy laws and protections than Participant’s country. Participant understands that if he or she resides outside the United States, he or she may request a list with the names and addresses of any potential recipients of the Data by contacting his or her local human resources representative. Participant authorizes the Company, the stock plan service provider as may be designated by the Company from time to time, and its affiliates, and any other possible recipients which may assist the Company (presently or in the future) with implementing, administering and managing the Plan to receive, possess, use, retain and transfer the Data, in electronic or other form, for the purposes of implementing, administering and managing Participant’s participation in the Plan. Participant understands that Data will be held only as long as is necessary to implement, administer and manage Participant’s participation in the Plan, and Participant’s participation in other Company human resources and finance administered programs including but not limited to payroll, health care insurance, and the Company’s 401(k) program. Participant understands that if he or she resides outside the United States, he or she may, at any time, view Data, request additional information about the storage and processing of Data, require any necessary amendments to Data or refuse or withdraw the consents herein, in any case without cost, by contacting in writing his or her local human resources representative. Further, Participant understands that he or she is

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providing the consents herein on a purely voluntary basis. For more information on the consequences of Participant’s refusal to consent or withdrawal of consent, Participant understands that he or she may contact his or her local human resources representative.

11. Language. If Participant has received this Agreement or any other document related to the Plan translated into a language other than English and if the meaning of the translated version is different than the English version, the English version will control.

12. Appendix. Notwithstanding any provisions in this Agreement, the RSU grant will be subject to any special terms and conditions set forth in any appendix to this Agreement for Participant’s country. Moreover, if Participant relocates to one of the countries included in the Appendix, the special terms and conditions for such country will apply to Participant, to the extent the Company determines that the application of such terms and conditions is necessary or advisable for legal or administrative reasons. The Appendix constitutes part of this Agreement.

13. Imposition of Other Requirements. The Company reserves the right to impose other requirements on Participant’s participation in the Plan, on the RSUs and on any Shares acquired under the Plan, to the extent the Company determines it is necessary or advisable for legal or administrative reasons, and to require Participant to sign any additional agreements or undertakings that may be necessary to accomplish the foregoing.

14. Acknowledgement. The Company and Participant agree that the RSUs are granted under and governed by the Notice, this Agreement and the provisions of the Plan. Participant: (a) acknowledges receipt of a copy of the Plan and the Plan prospectus, (b) represents that Participant has carefully read and is familiar with their provisions, and (c) hereby accepts the RSUs subject to all of the terms and conditions set forth herein and those set forth in the Plan and the Notice.

15. Entire Agreement; Enforcement of Rights. This Agreement, the Plan and the Notice constitute the entire agreement and understanding of the parties relating to the subject matter herein and supersede all prior discussions between them. Any prior agreements, commitments or negotiations concerning the purchase of the Shares hereunder are superseded. No modification of or amendment to this Agreement, nor any waiver of any rights under this Agreement, will be effective unless in writing and signed by the parties to this Agreement. The failure by either party to enforce any rights under this Agreement will not be construed as a waiver of any rights of such party.

16. Compliance with Laws and Regulations. The issuance of Shares will be subject to and conditioned upon compliance by the Company and Participant with all applicable state and federal laws and regulations and with all applicable requirements of any stock exchange or automated quotation system on which the Company’s Common Stock may be listed or quoted at the time of such issuance or transfer. Participant understands that the Company is under no obligation to register or qualify the Common Stock with any state, federal or foreign securities commission or to seek approval or clearance from any governmental authority for the issuance or sale of the Shares. Further, Participant agrees that the Company shall have unilateral authority to amend the Plan and this RSU Agreement without Participant’s consent to the extent necessary to comply with securities or other laws applicable to issuance of Shares. Finally, the Shares issued pursuant to this RSU Agreement shall be endorsed with appropriate legends, if any, determined by the Company.

17. Severability. If one or more provisions of this Agreement are held to be unenforceable under applicable law, the parties agree to renegotiate such provision in good faith. In the event that the parties cannot reach a mutually agreeable and enforceable replacement for such provision, then (a) such provision will be excluded from this Agreement, (b) the balance of this Agreement will be interpreted as if such provision were so excluded and (c) the balance of this Agreement will be enforceable in accordance with its terms.

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18. Governing Law and Venue. This Agreement and all acts and transactions pursuant hereto and the rights and obligations of the parties hereto will be governed, construed and interpreted in accordance with the laws of the State of Washington, without giving effect to principles of conflicts of law.

Any and all disputes relating to, concerning or arising from this Agreement, or relating to, concerning or arising from the relationship between the parties evidenced by the Plan or this Agreement, will be brought and heard exclusively in the United States District Court for the Western District of Washington or the courts of King County, Washington. Each of the parties hereby represents and agrees that such party is subject to the personal jurisdiction of said courts; hereby irrevocably consents to the jurisdiction of such courts in any legal or equitable proceedings related to, concerning or arising from such dispute, and waives, to the fullest extent permitted by law, any objection which such party may now or hereafter have that the laying of the venue of any legal or equitable proceedings related to, concerning or arising from such dispute which is brought in such courts is improper or that such proceedings have been brought in an inconvenient forum.

19. No Rights as Employee, Director or Consultant. Nothing in this Agreement will affect in any manner whatsoever the right or power of the Company, or a Parent or Subsidiary of the Company, to terminate Participant’s Service, for any reason, with or without Cause.

20. Consent to Electronic Delivery of All Plan Documents and Disclosures. By Participant’s acceptance (whether in writing, electronically or otherwise) of the Notice, Participant and the Company agree that the RSUs are granted under and governed by the terms and conditions of the Plan, the Notice and this Agreement. Participant has reviewed the Plan, the Notice and this Agreement in their entirety, has had an opportunity to obtain the advice of counsel prior to executing this Agreement, and fully understands all provisions of the Plan, the Notice and this Agreement. Participant hereby agrees to accept as binding, conclusive and final all decisions or interpretations of the Committee upon any questions relating to the Plan, the Notice and this Agreement. Participant further agrees to notify the Company upon any change in Participant’s residence address. By acceptance of the RSUs, Participant agrees to participate in the Plan through an on-line or electronic system established and maintained by the Company or a third party designated by the Company and consents to the electronic delivery of the Notice, this Agreement, the Plan, account statements, Plan prospectuses required by the U.S. Securities and Exchange Commission, U.S. financial reports of the Company, and all other documents that the Company is required to deliver to its security holders (including, without limitation, annual reports and proxy statements) or other communications or information related to the RSUs and current or future participation in the Plan. Electronic delivery may include the delivery of a link to the Company intranet or the internet site of a third party involved in administering the Plan, the delivery of the document via e-mail or such other delivery determined at the Company’s discretion. Participant acknowledges that Participant may receive from the Company a paper copy of any documents delivered electronically at no cost if Participant contacts the Company by telephone, through a postal service or electronic mail to Stock Administration. Participant further acknowledges that Participant will be provided with a paper copy of any documents delivered electronically if electronic delivery fails; similarly, Participant understands that Participant must provide on request to the Company or any designated third party a paper copy of any documents delivered electronically if electronic delivery fails. Also, Participant understands that Participant’s consent may be revoked or changed, including any change in the electronic mail address to which documents are delivered (if Participant has provided an electronic mail address), at any time by notifying the Company of such revised or revoked consent by telephone, postal service or electronic mail through Stock Administration. Finally, Participant understands that Participant is not required to consent to electronic delivery if local laws prohibit such consent.

21. Insider Trading Restrictions/Market Abuse Laws. Participant acknowledges that, depending on Participant’s country, Participant may be subject to insider trading restrictions and/or market abuse laws, which may affect Participant’s ability to acquire or sell the Shares or rights to Shares under the Plan during such times as Participant is considered to have “inside information” regarding the Company (as defined by the laws in Participant’s country). Any restrictions under these laws or regulations are separate from and in addition to any restrictions that may be imposed under any applicable Company insider trading policy. Participant acknowledges that it is Participant’s responsibility to comply with any applicable restrictions, and Participant is advised to speak to Participant’s personal advisor on this matter.

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22. Code Section 409A. For purposes of this Agreement, a termination of employment will be determined consistent with the rules relating to a “separation from service” as defined in Section 409A of the Internal Revenue Code and the regulations thereunder (“Section 409A”). Notwithstanding anything else provided herein, to the extent any payments provided under this RSU Agreement in connection with Participant’s termination of employment constitute deferred compensation subject to Section 409A, and Participant is deemed at the time of such termination of employment to be a “specified employee” under Section 409A, then such payment shall not be made or commence until the earlier of (i) the expiration of the six-month period measured from Participant’s separation from service from the Company or (ii) the date of Participant’s death following such a separation from service; provided, however, that such deferral shall only be effected to the extent required to avoid adverse tax treatment to Participant including, without limitation, the additional tax for which Participant would otherwise be liable under Section 409A(a)(1)(B) in the absence of such a deferral. To the extent any payment under this RSU Agreement may be classified as a “short-term deferral” within the meaning of Section 409A, such payment shall be deemed a short-term deferral, even if it may also qualify for an exemption from Section 409A under another provision of Section 409A. Payments pursuant to this section are intended to constitute separate payments for purposes of Section 1.409A-2(b)(2) of the Treasury Regulations.

23. Award Subject to Company Clawback or Recoupment. Notwithstanding any other provision in an employment offer letter or agreement or a severance or change in control plan, this RSU will be subject to clawback or recoupment in accordance with any clawback policy adopted by the Board, required by the listing standards of any national securities exchange or association on which the Company’s securities are listed or as is required by other applicable law, including, but not limited to, the cancellation of Participant’s outstanding RSU (whether vested or unvested) and the recoupment of any gains realized with respect to Participant’s RSU. No recovery of compensation under such policy or applicable law will be an event giving rise to a right to resign for “good reason” or “constructive termination” (or similar term) under any agreement with the Company.

BY ACCEPTING THIS AWARD OF RSUS, PARTICIPANT AGREES TO ALL OF THE TERMS AND CONDITIONS DESCRIBED ABOVE AND IN THE PLAN.

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CASCADIAN THERAPEUTICS, INC.

2016 EQUITY INCENTIVE PLAN

RESTRICTED STOCK UNIT AWARD AGREEMENT

COUNTRY SPECIFIC PROVISIONS FOR PARTICIPANTS OUTSIDE THE U.S.

Terms and Conditions

This Appendix includes additional terms and conditions that govern the RSUs granted to Participant under the Plan if Participant resides and/or works in one of the countries below. This Appendix forms part of the Agreement. Any capitalized term used in this Appendix without definition will have the meaning ascribed to it in the Notice, the Agreement or the Plan, as applicable.

If Participant is a citizen or resident of a country, or is considered resident of a country, other than the one in which Participant is currently working, or Participant transfers employment and/or residency between countries after the Date of Grant, the Company will, in its sole discretion, determine to what extent the additional terms and conditions included herein will apply to Participant under these circumstances.

Notifications

This Appendix also includes information relating to exchange control and other issues of which Participant should be aware with respect to Participant’s participation in the Plan. The information is based on the securities, exchange control and other laws in effect in the respective countries as of March 2016. Such laws are often complex and change frequently. As a result, the Company strongly recommends that Participant not rely on the information herein as the only source of information relating to the consequences of Participant’s participation in the Plan because the information may be out of date at the time that Participant vests in the RSUs or sells Shares acquired under the Plan.

In addition, the information is general in nature and may not apply to Participant’s particular situation, and the Company is not in a position to assure Participant of any particular result. Accordingly, Participant is advised to seek appropriate professional advice as to how the relevant laws in Participant’s country may apply to Participant’s situation.

Finally, if Participant is a citizen or resident of a country, or is considered resident of a country, other than the one in which Participant is currently working, or Participant transfers employment and/or residency after the Date of Grant, the information contained herein may not apply to Participant in the same manner.

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CASCADIAN THERAPEUTICS, INC.

2016 EQUITY INCENTIVE PLAN

RESTRICTED STOCK UNIT AWARD AGREEMENT

COUNTRY SPECIFIC PROVISIONS FOR PARTICIPANTS OUTSIDE THE U.S.

None

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