Company: RCUS
Filing Date: 2025-02-18
Form Type: 424B5
Source: 0001193125-25-028669
Chunk: 2

Company: Arcus Biosciences, Inc.
Filing Date: 2025-02-18
Form: 424B5
Chunk 2
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 supplement and the accompanying prospectus do not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any
securities offered by this prospectus supplement and the accompanying prospectus by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.

This prospectus supplement and the accompanying prospectus contain and incorporate by reference market data and industry statistics and forecasts that are
based on independent industry publications and other publicly available information. Although we believe that these sources are reliable, we do not guarantee the accuracy or completeness of this information and we have not independently verified
this information. Although we are not aware of any misstatements regarding the market and industry data presented in this prospectus supplement, the accompanying prospectus and the documents incorporated herein by reference, these estimates involve
risks and uncertainties and are subject to change based on various factors, including those discussed under the heading “Risk Factors” and elsewhere in this prospectus supplement, the accompanying prospectus and any related free

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writing prospectus, and under similar headings in the other documents that are incorporated by reference into this prospectus supplement and the accompanying prospectus. Accordingly, investors
should not place undue reliance on this information.

Except as otherwise indicated herein or as the context otherwise requires, references in this
prospectus supplement, the accompanying prospectus and any related free writing prospectus we authorize for use to “Arcus,” “the company,” “we,” “us,” “our” and similar references refer to Arcus
Biosciences, Inc., a corporation under the laws of the State of Delaware, and its wholly owned subsidiaries.

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PROSPECTUS SUPPLEMENT SUMMARY

This summary highlights certain information about us, this offering and selected information contained elsewhere in or incorporated by reference into this prospectus supplement and the accompanying prospectus. This summary is not complete and does not contain all of the information that you should consider before deciding whether to invest in our common stock. For a more complete understanding of our company and this offering, you should read and consider carefully the more detailed information included or incorporated by reference in this prospectus supplement, the accompanying prospectus and any free writing prospectus that we have authorized for use in connection with this offering, including the factors described in the section titled “Risk Factors” in this prospectus supplement beginning on page S-8,along with our consolidated financial statements and notes to those consolidated financial statements and the other