The disclosure under the section entitled The Merger Background of the Merger is
hereby amended and supplemented by adding the following bolded and double underlined language to the sixth full paragraph on page 39 of the Definitive Proxy Statement:
On December 30, 2023, Cravath sent copies of retention agreements for Dr. Aung and Dr. Buechler to Skadden and a representative
of Johnson & Johnson sent each agreement to each of the individual employees. Other than the retention agreements with Dr. Aung and Dr. Buechler, none of Johnson &
Johnsons offers to acquire Ambrx mentioned management retention or equity participation in the combined company for Ambrx management, and there were no other discussions with Johnson & Johnson regarding potential post-closing employment of
Ambrx management.
The disclosure under the section entitled The Merger Background of the Merger is hereby amended and
supplemented by adding the following bolded and double underlined language in the first full paragraph on page 41 of the Definitive Proxy Statement:
Later on January 4, 2024, the Board of Directors held a meeting, which included members of Ambrx management and representatives from
Centerview and Skadden. Representatives from Centerview gave an update that Johnson & Johnson had made the January 3 Offer, and that, in Centerviews professional opinion, this was the best and final offer from Johnson &
Johnson. Some members of the Board of Directors discussed their concern that the December 22 Offer did not adequately capture the value of the Ambrx platform, but they were now comfortable that the January 3 Offer captured the value of the
platform and that the Board of Directors was pleased with the January 3 Offer. Mr. OConnor then summarized recent interactions with Party A and that he had communicated to Party A that another party was moving forward with
negotiations and process to an announcement at the 2024 JPM Conference, but noted that he had neither expressly communicated to Party A any deadlines nor requested that Party A make an offer by a specific date. Representatives from Skadden discussed
the Board of Directors obligations under Delaware law. The Board of Directors noted that Ambrx only had one offer on the table to consider at this time and that there was no certainty that Party A would ever submit an offer, even if given more
time. The Board of Directors considered, if Ambrx were to delay entering into a definitive agreement with Johnson & Johnson, the risks of leak, disruption to Ambrxs employees
and business and the fact that a delay could jeopardize the potential transaction with Johnson & Johnson. The Board of Directors also considered the fact that the proposed merger agreement provided the ability for Ambrx to respond to
unsolicited acquisition proposals and change the Board of Directors recommendation to accept a Superior Proposal in certain circumstances specified in the Merger Agreement (and discussed in the sections of this proxy statement captioned
The Merger Agreement Acquisition Proposals and
The Merger Agreement The Board of Directors Recommendation; Company Board Recommendation
Change), if Party A, or any other potentially interested party, submitted a proposal after the execution of the proposed merger agreement with Johnson &
Johnson. The Board of Directors agreed that management should continue to progress the Johnson & Johnson transaction and continue discussions with Party A without setting any formal deadlines.
Opinion of Ambrxs Financial Advisor - Centerview Partners LLC
The disclosure under the section entitled The Merger Opinion of Ambrxs Financial Advisor Centerview Partners LLC is
hereby amended and supplemented by adding the following bolded and double underlined language in the second full paragraph on page 51 of the Definitive Proxy Statement:
In performing this analysis, Centerview calculated a range of equity values for the shares of our common stock by (a) discounting to
present value, as of December 31, 2023, using discount rates ranging from 14.0% to 16.0% (based on Centerviews analysis of Ambrxs weighted average cost of capital and other
considerations that Centerview deemed relevant in its professional judgment and experience) and using a mid-year convention: (i) the forecasted risk-adjusted,
after-tax unlevered free cash flows of Ambrx over the period beginning on January 1, 2024 and ending on December 31, 2045, utilized by Centerview based on the Projections, (ii) an implied
terminal value of Ambrx, calculated by Centerview by assuming, based on its analysis and other considerations that Centerview
deemed relevant in its professional judgment and experience, as directed by Ambrxs management, that Ambrxs unlevered free cash flows would decline in perpetuity after December 31, 2045 at a rate of free cash flow decline of
50% year-over-year and (iii) tax savings from usage of Ambrxs estimated federal net operating losses of approximately
$211 million as of December 31, 2022 and Ambrxs future losses, as set forth in the Projections, and
(b) adding to the foregoing results Ambrxs estimated net cash balance of approximately
$197 million as of December 31, 2023, as provided by Ambrxs management, and (c) subtracting from the
foregoing results the present value of the impact of assumed equity raises of approximately $875 million in aggregate gross proceeds in 2024, 2025, 2026 and 2027, as instructed
by Ambrxs management.
The disclosure under the section entitled The Merger Opinion of Ambrxs Financial Advisor
Centerview Partners LLC is hereby amended and supplemented by adding the following bolded and double underlined language and deleting the following strikethrough language in the third full paragraph on page 51 of the Definitive Proxy
Statement:
Centerview then calculated a range of implied equity values per share of our common stock by dividing the result of the
foregoing calculations by the number of fully-diluted outstanding shares of our common stock (determined using the treasury stock method basis and taking into account outstanding in-the-money options, restricted stock units and other shares issuable
in a change of control transaction) as of January 43, 2024, and as set forth in the Internal Data. The resulting range of implied equity values per share of our
common stock was $19.30 $23.45, rounded to the nearest $0.05. Centerview then compared the results of the above analysis to the Merger Consideration of $28.00 per share to be paid to the holders of shares of our common stock (other than
Excluded Shares) pursuant to the Merger Agreement.
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