Description of Securities

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EXHIBIT 4.3

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DESCRIPTION OF SECURITIES

REGISTERED PURSUANT TO SECTION 12 OF THE SECURITIES

EXCHANGE ACT OF 1934

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Common Stock

The following description is based on relevant portions of the Delaware General Corporation Law (the “DGCL”) and our Fourth Amended and Restated Certificate of Incorporation (the “Certificate of Incorporation”). This summary is a description of the material terms of, and is qualified in its entirety by, reference to our Certificate of Incorporation, a copy of which is filed as an exhibit to our previous filings with the SEC and incorporated by reference to the Annual Report on Form 10-K of which this Description of Securities is attached as an exhibit.

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Authorization; Outstanding Shares. We are authorized to issue 200,000,000 shares of common stock, par value $0.0001 per share, of which 8,811,423 shares were issued and outstanding as of March 18, 2022. We may amend from time to time our Certificate of Incorporation to increase the number of authorized shares of common stock. Any such amendment would require the approval of the holders of a majority of the voting power of the shares entitled to vote thereon.

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Voting Rights. Holders of our common stock are entitled to one (1) vote for each share on all matters submitted to a stockholder vote. The common stock does not have cumulative voting rights. Therefore, holders of a majority of the shares of common stock voting for the election of directors can elect all of the directors. Holders of our common stock representing a majority of the voting power of our capital stock issued, outstanding and entitled to vote, represented in person or by proxy, are necessary to constitute a quorum at any meeting of stockholders.

Dividends.  Subject to limitations under Delaware law and the rights of holders of any class of stock having preference over our common stock, holders of our common stock are entitled to share in all dividends that our board of directors, in its discretion, declares from legally available funds.

Liquidation; Dissolution. In the event of a liquidation, dissolution or winding up, each outstanding share entitles its holder to participate pro rata in all assets that remain after payment of liabilities and after providing for each class of stock, if any, having preference over the common stock.

Other Rights and Restrictions.  Our common stock has no pre-emptive rights, no conversion rights and there are no redemption provisions or sinking fund provisions applicable to the common stock.

Listing. Our common stock is quoted on the Nasdaq Capital Market under the symbol “ISPC.” As of March 18, 2022, there were 67 record holders of our common stock.

Transfer Agent and Registrar. The transfer agent and registrar for our common stock is Continental Stock Transfer & Trust. The transfer agent and registrar’s address is 1 State Street, 30^th Floor, New York, NY 10004 and its telephone number is ###-###-####.

Anti-Takeover Provisions

Provisions of our Certificate of Incorporation and Second Amended and Restated Bylaws (“Bylaws”) could make it more difficult to acquire us by means of a merger, tender offer, proxy contest, open market purchases, removal of incumbent directors and otherwise. These provisions, which are summarized below, are expected to discourage types of coercive takeover practices and inadequate takeover bids and to encourage persons seeking to acquire control of us to first negotiate with us. We believe that the benefits of increased protection of our potential ability to negotiate with the proponent of an unfriendly or unsolicited proposal to acquire or restructure us outweigh the disadvantages of discouraging takeover or acquisition proposals because negotiation of these proposals could result in an improvement of their terms.

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Vacancies.  Newly created directorships resulting from any increase in the number of directors and any vacancies on the board of directors resulting from death, resignation, disqualification, removal or other cause shall be filled by a majority of the remaining directors on the board.

Bylaws.  Our Certificate of Incorporation and Bylaws authorize the board of directors to adopt, repeal, rescind, alter or amend our bylaws without stockholder approval.

Removal.  Except as otherwise provided, a director may be removed from office only by the affirmative vote of the holders of not less than a majority of the voting power of the issued and outstanding stock entitled to vote.

Calling of Special Meetings of Stockholders.  Our Bylaws provide that special meetings of stockholders for any purpose or purposes may be called at any time only by the board of directors or by our Secretary following receipt of one or more written demands from stockholders of record who own, in the aggregate, at least 15% the voting power of our outstanding stock then entitled to vote on the matter or matters to be brought before the proposed special meeting.

Cumulative Voting.  Our certificate of Incorporation does not provide for cumulative voting in the election of directors, which would allow holders of less than a majority of the stock to elect some directors.

Staggered Board.  Our Bylaws provide for a board of directors divided into three classes with only one class of directors being elected in each year and each class (except for those directors appointed prior to our 2022 annual meeting of stockholders) serving a three-year term. As a result, only a minority of the board of directors will be considered for election at every annual meeting of stockholders, which may make the removal of management more difficult and may discourage transactions that otherwise could involve payment of a premium over prevailing market prices for our securities.