X0206 3 2021-03-11 0 0001718852 Prometheus Biosciences, Inc. RXDX 0000792990 NESTLE SA AVENUE NESTLE 55 CH-1800, VEVEY V8 SWITZERLAND 0 0 1 0 0001803539 Societe des Produits Nestle S.A. AVENUE NESTLE 55 CH-1800, VEVEY V8 SWITZERLAND 0 0 1 0 Series C Convertible Preferred Stock Common Stock 2500000 I See Footnote Series D-1 Convertible Preferred Stock Common Stock 508885 I See Footnote Series D-2 Convertible Preferred Stock Common Stock 721956 I See Footnote Shares of Series C Preferred Stock are convertible at any time, at the holder's election, at a ratio of ten-for-one share of the Issuer's common stock. In addition, effective immediately prior to the closing of the Issuer's initial public offering of its common stock, each share of Series C Preferred Stock will automatically convert at the ratio of ten-for-one share of the Issuer's common stock. The Series C Preferred Stock has no expiration date. Shares of Series D-1 Preferred Stock are convertible at any time, at the holder's election, at a ratio of ten-for-one share of the Issuer's common stock. In addition, effective immediately prior to the closing of the Issuer's initial public offering of its common stock, each share of Series D-1 Preferred Stock will automatically convert at the ratio of ten-for-one share of the Issuer's common stock. The Series D-1 Preferred Stock has no expiration date. Shares of Series D-2 Preferred Stock are convertible at any time, at the holder's election, at a ratio of ten-for-one share of the Issuer's common stock. In addition, effective immediately prior to the closing of the Issuer's initial public offering of its common stock, each share of Series D-2 Preferred Stock will automatically convert at the ratio of ten-for-one share of the Issuer's common stock. The Series D-2 Preferred Stock has no expiration date. The shares reported herein represent, (i) 855,000 shares of Series C Preferred Stock held by Nestle Health Science US Holdings, Inc. ("NHS"), (ii) 508,885 shares of Series D-1 Preferred Stock held by NHS, (iii) 721,956 shares of Series D-2 Preferred Stock held by NHS and (iv) 1,645,000 shares of Series C Preferred Stock held by Societe des Produits Nestle S.A. ("SPN"). NHS is a wholly owned subsidiary of NIMCO US, Inc. ("NIMCO"). NIMCO, in turn, is a wholly-owned subsidiary of Nestle US Holdco, Inc. ("Nestle US Holdco"), which is a wholly-owned subsidiary of SPN. The ultimate parent company of NHS, NIMCO, Nestle US Holdco and SPN is Nestle S.A. ("Nestle"). Each of these entities may be deemed to share voting and investment power with respect to all shares of Series C Preferred Stock, Series D-1 Preferred Stock and Series D-2 Preferred Stock held by NHS. (Continued from Footnote 4) Additionally, Nestle may be deemed to share voting and investment power with respect to all shares of Series C Preferred Stock held by SPN. SOCIETE DES PRODUITS NESTLE S.A. By: /s/ Claudio Kuoni, Name: Claudio Kuoni, Title: Vice President 2021-03-11 NESTLE S.A. By: /s/ Gregory Behar, Name: Gregory Behar, Title: Deputy Executive Vice President 2021-03-11