Form of Proxy

The Company seeks shareholder approval under Nasdaq Listing Rule 5635(d) because Proposal No. 1 could result in issuing over 20% of its pre-Exchange Offer outstanding common stock. The potential issuance relates to conversion of up to $72.0 million of 7.50% Convertible Senior Secured First Lien Notes due 2030, possible share-based make-whole payments, and exercise of 135,789,000 warrants.

To approve an amendment and restatement of the Gossamer Bio, Inc. 2019 Incentive Award Plan (the Restated Plan) to increase the number of shares of Common Stock authorized for issuance thereunder, as described in Proposal No. 2 in the accompanying proxy statement.

To approve an amendment to the Companys amended and restated certificate of incorporation (the Charter), to increase the number of authorized shares of Common Stock from 700,000,000 to 4,000,000,000 in order to support, among other things, the additional share issuances of Common Stock issuable upon conversion of the New Convertible Notes and Purchase Warrants and under the Restated Plan, as described in Proposal No. 3 in the accompanying proxy statement.

To approve a series of 30 alternate amendments to the Charter to effect (i) a reverse stock split of our issued and outstanding shares of Common Stock and (ii) a proportionate reduction in the number of authorized shares of Common Stock (and correspondingly decrease the total number of authorized shares of our capital stock), as described in Proposal No. 4 in the accompanying proxy statement.

To approve one or more adjournments of the Special Meeting, if necessary, to solicit additional proxies if there are not sufficient votes to approve the foregoing proposals at the Special Meeting or any adjournment(s) thereof, as described in Proposal No. 5 in the accompanying proxy statement.