v3.26.1
Stockholders' Equity
 6 Months Ended
Jun. 30, 2026
Stockholders' Equity Note [Abstract]  
Stockholders’ Equity Stockholders’ Equity
Authorized Share Capital and Preferred Stock
The Company’s authorized share capital consists of 1,000,000,000 shares of stock, consisting of (i) 900,000,000 shares of common stock, par value $0.00001 per share, and (ii) 100,000,000 shares of preferred stock, par value $0.00001 per share.
On October 13, 2022, the Company completed an internal reorganization transaction resulting in a Delaware incorporated entity becoming the listed company (the “Redomicile Transactions”). Prior to the Redomicile Transactions, the shares of Zymeworks BC Inc. (formerly known as Zymeworks Inc.) were publicly listed. To effect the Redomicile Transactions, the Company conducted a share exchange, pursuant to which holders of the Company’s common shares exchanged their common shares in the Company for shares of common stock of Zymeworks Inc. (formerly known as Zymeworks Delaware Inc.) or, at their election with respect to all or a portion of their common shares in the Company and subject to applicable eligibility criteria and an overall cap, exchangeable shares (the “Exchangeable Shares”) in the capital of a newly formed indirect subsidiary of Zymeworks Inc. A special meeting of Company security holders was held on October 7, 2022 to approve the Redomicile Transactions. The Redomicile Transactions were governed by a transaction agreement dated July 14, 2022, as restated and amended on August 18, 2022 (the “Restated and Amended Transaction Agreement”), by and among the Company and its direct or indirect subsidiaries Zymeworks Inc., Zymeworks CallCo ULC (“CallCo”) and Zymeworks ExchangeCo Ltd., (“ExchangeCo”) including a plan of arrangement included as Exhibit A to the Restated and Amended Transaction Agreement (the “Plan of Arrangement”).
In connection with the Plan of Arrangement, the Company issued to Computershare Trust Company of Canada, a trust company existing under the laws of Canada (the “Share Trustee”), one share of the Company’s preferred stock, par value $0.00001 per share, which has certain variable voting rights in proportion to the number of Exchangeable Shares outstanding (the “Special Voting Preferred Stock”), enabling the Share Trustee to exercise voting rights for the benefit of the holders of the Exchangeable Shares.
Immediately prior to the completion of the Redomicile Transactions, there were 61,699,387 Zymeworks BC common shares issued and outstanding. In connection with the consummation of the Plan of Arrangement, 60,274,854 shares of common stock and 1,424,533 Exchangeable Shares were issued to former Zymeworks BC shareholders. As of June 30, 2026, there were 550,000 Exchangeable Shares held by former Zymeworks BC shareholders (December 31, 2025: 553,184). The Company will issue shares of its common stock as consideration when a holder of Exchangeable Shares calls for Exchangeable Shares to be retracted by ExchangeCo, when ExchangeCo redeems Exchangeable Shares from the holder, or when CallCo purchases Exchangeable Shares from the Exchangeable Shareholder under CallCo’s overriding call rights. These Exchangeable Shares and the Special Voting Preferred Stock, when taken together, are similar in substance to the Company’s common stock and are treated as such in calculation of basic net loss per share.
2024 Repurchase Program
On August 1, 2024, the board of directors of the Company authorized a stock repurchase program (the “2024 Repurchase Program”), whereby the Company may repurchase up to $60,000 of the Company’s outstanding common stock, par value $0.00001 per share.
During the year ended December 31, 2024, the Company repurchased 2,545,402 shares of its common stock for a cost of $30,000, and incurred commission expense of $51, under the 2024 Repurchase Program, which have been recorded against accumulated deficit. The Company’s share repurchases in excess of issuances are subject to a 1% excise tax enacted by the Inflation Reduction Act of $152. During the year ended December 31, 2024, the Company retired all 2,545,402 shares repurchased. These shares were returned to the status of authorized and unissued shares. During the year ended December 31, 2025, the Company completed the 2024 Repurchase Program by repurchasing 1,856,907 shares of its common stock for a cost of $29,997 and incurred commission expense of $37, which have been recorded against accumulated deficit. Excise tax was estimated as nil. The Company retired all 1,856,907 shares repurchased. These shares were returned to the status of authorized and unissued shares.
The following table presents the Company’s 2024 Repurchase Program activity:
Total number of shares purchasedAverage price paid per shareApproximate value of shares purchased
Year Ended December 31, 20242,545,402 $11.79 $30,000 
Year Ended December 31, 20251,856,907 $16.15 $29,997 
2025 Repurchase Program and 2026 Repurchase Program
On November 16, 2025, the board of directors of the Company authorized a new stock repurchase program (the “2025 Repurchase Program”), whereby the Company may repurchase up to $125,000 of the Company’s outstanding common stock, par value $0.00001 per share.
During the year ended December 31, 2025, the Company repurchased 431,217 shares of its common stock for a cost of $11,188, incurred an obligation to purchase common stock for a cost of $464 which had not been settled by December 31, 2025, and incurred commission expense of $9, under the 2025 Repurchase Program, which have been recorded against accumulated deficit. Excise tax was estimated as nil. The Company retired all 431,217 shares repurchased. These shares were returned to the status of authorized and unissued shares.
During the six months ended June 30, 2026, the Company repurchased 3,766,336 shares of its common stock for a cost of $91,069, and incurred commission expense of $75, under the 2025 Repurchase Program, which have been recorded against accumulated deficit. The Company retired all 3,766,336 shares repurchased. These shares were returned to the status of authorized and unissued shares.
The following table presents the Company’s 2025 Repurchase Program activity for the periods indicated:
Total number of shares purchasedAverage price paid per shareApproximate value of shares purchased
Year Ended December 31, 2025431,217 $25.94 $11,188 
Six Months Ended June 30, 2026
3,766,336 $24.18 $91,069 
On May 14, 2026, the Company terminated the 2025 Repurchase Program and the board of directors of the Company authorized a new share repurchase program providing the ability to repurchase up to $125.0 million in shares of the Company's common stock (the “2026 Repurchase Program”).
During the six months ended June 30, 2026, the Company repurchased 2,008,243 shares of its common stock for a cost of $51,908, incurred an obligation to purchase common stock for a cost of $1,996 which had not been settled by June 30, 2026, and incurred commission expense of $42, under the 2026 Repurchase Program, which have been recorded against accumulated deficit. The Company retired all 2,008,243 shares repurchased. These shares were returned to the status of authorized and unissued shares.
Excise tax was estimated as $797 during the six months ended June 30, 2026, for purchases under the 2025 Repurchase Program and 2026 Repurchase Program.
The following table presents the Company’s 2026 Repurchase Program activity:
Total number of shares purchasedAverage price paid per shareApproximate value of shares purchased
Six Months Ended June 30, 2026
2,008,243 $25.85 $51,908 
Stock-Based Compensation
In connection with Redomicile Transactions in 2022, Zymeworks BC assigned to the Company, and the Company assumed, all of Zymeworks BC’s rights and obligations under each of the stock-based compensation plans, as described below, and such plans became the Company’s stock-based compensation plans, with each outstanding award assumed by the Company and deemed exchanged for equivalent awards of the Company, except that the security issuable upon exercise or settlement, as applicable, will be shares of common stock of the Company rather than common shares of Zymeworks BC.
Original Stock Option Plan
On July 14, 2006, the shareholders of the Company approved an employee stock option plan (the “Original Plan”). The total number of options outstanding is not to exceed 20% of the issued common shares of the Company. Options granted under the Original Plan are exercisable at various dates over their 10-year life. The exercise prices of the Company’s stock options under the Original Plan are denominated in Canadian dollars. Upon the effectiveness of the Company’s New Plan described below, no further options were issuable under the Original Plan. However, all outstanding options granted under the Original Plan remain outstanding, subject to the terms of the Original Plan and the applicable grant documents, until such outstanding options are exercised or they terminate or expire by their terms.
New Plan and Inducement Plan
On April 10, 2017, the Company’s shareholders approved a new stock option plan, which became effective immediately prior to the consummation of the Company’s initial public offering (“IPO”). This plan allows for the grant of options and also permitted the Company to grant incentive stock options (“ISOs”), within the meaning of Section 422 of the Internal Revenue Code, to its employees, until the shares reserved for issuance of ISOs were depleted. On June 7, 2018, the Company’s shareholders approved an amendment and restatement of this plan (this plan, as amended and restated, the “New Plan”), which includes an article that allows the Company to grant restricted shares, RSU, PSU and other share-based awards, in addition to stock options. As of June 30, 2026, 5,190,276 shares of common stock were available for future award grants under the New Plan (December 31, 2025: 5,023,809 shares of common stock).
On January 5, 2022, the board of directors approved the Zymeworks Inc. Inducement Stock Option and Equity Compensation Plan (the “Inducement Plan”) and reserved 750,000 of the Company’s common shares for issuance pursuant to equity awards granted thereunder. On July 19, 2024, the board of directors approved an amendment and restatement of the Inducement Plan, which increased the number of shares of the Company’s common stock available for future issuance pursuant to equity awards granted under the Inducement Plan by 700,000 shares. As a result of this increase, a total of 1,450,000 shares will have been available for issuance pursuant to equity awards granted under the Inducement Plan since the inception of the Inducement Plan in January 2022. As of June 30, 2026, 622,500 shares of common stock were available for future award grants under this plan (December 31, 2025: 390,000).
RSUs
The following table summarizes the Company’s RSU activity under the New Plan since December 31, 2025:
Number of RSUsWeighted-
average grant
date fair value
($)
Outstanding, December 31, 20251,947,584 12.90 
Granted1,374,700 23.91 
Vested and settled(796,552)11.33 
Cancelled, expired(254,154)16.77 
Outstanding, June 30, 20262,271,578 19.68 
As of June 30, 2026, there was $25,108 of unamortized RSU expense that will be recognized over a weighted average period of 1.92 years.
PSUs
The following table summarizes the Company’s PSU activity under the New Plan since December 31, 2025:
Number of RSUsWeighted-
average grant
date fair value
($)
Outstanding, December 31, 2025— — 
Granted317,000 34.45 
Outstanding, June 30, 2026317,000 34.45 
As of June 30, 2026, there was $9,473 of unamortized PSU expense that will be recognized over a weighted average period of 2.61 years.
Stock Options
The following table summarizes the Company’s stock options granted in Canadian dollars under the Original Plan and the New Plan:
Number
of Options		Weighted-
Average
Exercise Price
($)		Weighted-
Average
Contractual
Term
(years)		Aggregate
intrinsic value
($)
Outstanding, December 31, 2025572,112 18.17 4.316,081 
Granted— — 
Exercised(115,357)9.56 
Cancelled, expired(7,546)29.50 
Outstanding, June 30, 2026449,209 19.47 3.914,182 
The following table summarizes the Company’s stock options granted in U.S. dollars under the New Plan and the Inducement Plan:
Number
of Options		Weighted-
Average
Exercise Price
($)		Weighted-
Average
Contractual
Term
(years)		Aggregate
intrinsic value
($)
Outstanding, December 31, 20257,816,277 12.71 7.47109,157 
Granted2,005,750 23.83 
Exercised(1,003,662)10.46 
Cancelled, expired(892,327)14.77 
Outstanding, June 30, 20267,926,038 15.58 7.8286,336 
During the six months ended June 30, 2026, the Company received cash proceeds of $11,605 from stock options exercised.
The stock options outstanding at June 30, 2026 expire at various dates from November 9, 2026 to June 9, 2036.
The estimated fair values of options granted to officers, directors, employees and consultants are amortized over the relevant vesting periods. Stock-based compensation expense for equity classified instruments, RSUs, PSUs as well as the financial statement impact of the amortization and periodic revaluation of liability classified instruments, are recorded in research and development expense and general and administration expense as follows:
Three Months Ended June 30,Six Months Ended June 30,
2026202520262025
Research and development expense
$3,313 $2,891 $7,106 $6,052 
General and administrative expense
7,887 2,832 10,917 5,945 
The amounts above include stock-based compensation expense relating to RSUs and PSUs of $5,167 and $8,863 for the three and six months ended June 30, 2026, respectively (2025: $2,346 and $4,626).
The estimated fair value of stock options granted under the New Plan was determined using the Black-Scholes option pricing model with the following weighted-average assumptions:
Six Months Ended June 30,
20262025
Dividend yield0 %0 %
Expected volatility62.9 %63.1 %
Risk-free interest rate3.90 %4.49 %
Expected average life of options6.03 years6.06 years
The weighted-average Black-Scholes option pricing assumptions for liability classified stock options outstanding at June 30, 2026 and 2025 are as follows:
Six Months Ended June 30,
20262025
Dividend yield
0 %0 %
Expected volatility
45.1 %46.9 %
Risk-free interest rate
2.72 %2.60 %
Expected average option term
0.60 years0.56 years
Number of liability classified stock options outstanding
49,402272,330
At June 30, 2026, the unamortized compensation expense related to unvested options was $26,728. The remaining unamortized compensation expense as of June 30, 2026 will be recognized over a weighted-average period of 1.82 years.