The following represents the historical ordinary share transactions of the Company from December 31, 2015 through December 31, 2018:

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In May 2016, the Company granted 1,875,000 ordinary shares to Pfizer under the Pfizer Agreements (Note 5) at a purchase price of $16.00 per share, for an aggregate purchase price of $30.0 million.

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In April 2017, the Company closed a follow-on underwritten public offering of 4,166,667 ordinary shares at a purchase price of $24.00 per share for gross proceeds of $100.0 million. The net proceeds from this issuance were $93.5 million after deducting underwriting discounts and commissions and other offering expenses.

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In April 2018, the Company granted 1,096,892 ordinary shares to Takeda under the Takeda Collaboration Agreement (Note 5) at a purchase price of $54.70 per share, for an aggregate purchase price of $60.0 million.

The Series A preferred shares and ordinary shares have no par value and there is no concept of authorized share capital under Singapore law. The Series A preferred shares are not redeemable.

The holders of Series A preferred shares are not entitled to vote on any of the matters proposed to shareholders, other than as specified in the Company's Constitution. The holders of ordinary shares are entitled to one vote for each ordinary share held at all meetings of shareholders and written actions in lieu of meetings.

All dividends, if any, shall be declared and paid pro rata according to the number of shares held by each member entitled to receive dividends. The Company’s board of directors may deduct from any dividend all sums of money presently payable by the member to the Company on account of calls.

In the event of a liquidation, dissolution or winding up of, or a return of capital by the Company, the ordinary shares will rank equally with the Series A preferred shares after the payment of the liquidation preference of an aggregate of approximately $10 thousand for Series A preferred shares.