X0206 3 2021-03-02 0 0001315098 Roblox Corp RBLX 0001766317 Altos Ventures IV Liquidity Fund, L.P. 2882 SAND HILL ROAD, SUITE 100 MENLO PARK CA 94025 0 0 1 0 0001848632 Altos Hybrid 2 P-FIO, LLC 2882 SAND HILL ROAD, SUITE 100 MENLO PARK CA 94025 0 0 1 0 0001848637 Altos Hybrid 2 V, LLC 2882 SAND HILL ROAD, SUITE 100 MENLO PARK CA 94025 0 0 1 0 0001694364 Altos Hybrid 2, L.P. 2882 SAND HILL ROAD, SUITE 100 MENLO PARK CA 94025 0 0 1 0 0001848640 Altos Hybrid 3 B, LLC 2882 SAND HILL ROAD, SUITE 100 MENLO PARK CA 94025 0 0 1 0 0001848639 Altos Hybrid 3 M, LLC 2882 SAND HILL ROAD, SUITE 100 MENLO PARK CA 94025 0 0 1 0 0001848638 Altos Hybrid 3 W, LLC 2882 SAND HILL ROAD, SUITE 100 MENLO PARK CA 94025 0 0 1 0 0001848642 Altos Hybrid 4 GS, LLC 2882 SAND HILL ROAD, SUITE 100 MENLO PARK CA 94025 0 0 1 0 0001826414 Altos Hybrid 4, L.P. 2882 SAND HILL ROAD, SUITE 100 MENLO PARK CA 94025 0 0 1 0 0001828887 Altos Hybrid CC, LLC 2882 SAND HILL ROAD, SUITE 100 MENLO PARK CA 94025 0 0 1 0 Class A Common Stock 222222 I See Footnotes Class A Common Stock 111111 I See Footnotes Class A Common Stock 475582 I See Footnotes Class A Common Stock 222222 I See Footnotes Class A Common Stock 22222 I See Footnotes Class A Common Stock 111111 I See Footnotes Class A Common Stock 466666 I See Footnotes Class A Common Stock 111112 I See Footnotes Class A Common Stock 55555 I See Footnotes Class A Common Stock 344444 I See Footnotes Class A Common Stock 111111 I See Footnotes Class A Common Stock 27281228 I See Footnotes Class A Common Stock 3796276 I See Footnotes Class A Common Stock 18918191 I See Footnotes Class A Common Stock 40563924 I See Footnotes Class A Common Stock 848844 I See Footnotes Class A Common Stock 22600140 I See Footnotes These shares are held directly by Altos Hybrid 2 P-FIO LLC These shares are held directly by Altos Hybrid 2 V LLC These shares are held directly by Altos Hybrid 2, L.P. These shares are held directly by Altos Hybrid 3 B, LLC These shares are held directly by Altos Hybrid 3 M, LLC These shares are held directly by Altos Hybrid 3 W, LLC These shares are held directly by Altos Hybrid 4 GS, LLC These shares are held directly by Altos Hybrid 4, L.P. These shares are held directly by Altos Hybrid CC, LLC These shares are held directly by Altos Hybrid HG, LLC These shares are held directly by Altos Hybrid UP, LLC These shares are held directly by Altos Roblox SPV 1, LLC These shares are held directly by Altos Roblox SPV 2, LLC These shares are held directly by Altos Roblox SPV 2020, LLC These shares are held directly by Altos Ventures IV Liquidity Fund, L.P. These shares are held directly by Altos Ventures IV Reserve Fund, L.P. These shares are held directly by Altos Ventures IV, L.P. The general partner of Altos Hybrid 2, L.P. is Altos Hybrid 2, GP, LLC; the general partner of Altos Hybrid 4, L.P. is Altos Hybrid 4, GP, LLC; and the general partner of Altos Ventures IV Liquidity Fund, L.P., Altos Ventures IV Reserve Fund, L.P. and Altos Ventures IV, L.P. is Altos Management Partners IV, LLC (collectively, the General Partners). The manager of Altos Roblox SPV 1, LLC and Altos Roblox SPV 2, LLC is Altos Roblox Management Partners, LLC; the manager of Altos Roblox SPV 2020, LLC is Altos Roblox 2020 Management Partners, LLC; the manager of Altos Hybrid 4 GS, LLC and Altos Hybrid HG, LLC is Altos Hybrid 4, GP, LLC; the manager of Altos Hybrid 2 V, LLC and Altos Hybrid 2 P-FIO, LLC is Altos Hybrid 2 GP, LLC; the manager of Altos Hybrid 3 B, LLC, Altos 3 M, LLC and Altos Hybrid 3 W, LLC, is Altos Hybrid 3 GP, LLC; the manager of Altos Hybrid UP, LLC and Altos Hybrid CC, LLC is Altos Hybrid 4 GP, LLC (collectively, the Managers). (Continued form footnote 18) The General Partners and the Managers disclaim beneficial ownership of the shares reported herein except to the extent of their respective pecuniary interests therein, if any. The Managing Directors or Managing Members of the General Partners and the Managers of the Altos Funds are Anthony P. Lee, Han Kim and Hodong Nam who exercise investment and voting control over the shares held by the Altos Funds. Anthony P. Lee, a director of the Issuer, files separate Section 16 reports. Han Kim and Hondong Nam disclaim beneficial ownership of the shares held by the Altos Funds except to the extent of their respective pecuniary interest therein, if any. Form 1 of 3. /s/ Anthony P. Lee, Managing Director of Altos Hybrid 2 GP, LLC, the Manager of Altos Hybrid 2 P-FIO, LLC 2021-03-02 /s/ Anthony P. Lee, Managing Director of Altos Hybrid 2 GP, LLC, the Manager of Altos Hybrid 2 V, LLC 2021-03-02 /s/ Anthony P. Lee, Managing Director of Altos Hybrid 2 GP, LLC, the Manager of Altos Hybrid 2, L.P. 2021-03-02 /s/ Anthony P. Lee, Managing Member of Altos Hybrid 3 GP, LLC, the Manager of Altos Hybrid 3 B, LLC 2021-03-02 /s/ Anthony P. Lee, Managing Member of Altos Hybrid 3 GP, LLC, the Manager of Altos Hybrid 3 M, LLC 2021-03-02 /s/ Anthony P. Lee, Managing Member of Altos Hybrid 3 GP, LLC, the Manager of Altos Hybrid 3 W, LLC 2021-03-02 /s/ Anthony P. Lee, Managing Member of Altos Hybrid 4 GP, LLC, the Manager of Altos Hybrid 4 GS, LLC 2021-03-02 /s/ Anthony P. Lee, Managing Member of Altos Hybrid 4 GP, LLC, the General Partner of Altos Hybrid 4, L.P. 2021-03-02 /s/ Anthony P. Lee, Managing Member of Altos Hybrid 4 GP, LLC, the Manager of Altos Hybrid CC, LLC 2021-03-02