Common use of Preferred Stock Financing Clause in Contracts

Preferred Stock Financing. August 7, 2020 The undersigned hereby agrees to become a party to (i) that certain Series A Preferred Stock Purchase Agreement, as amended (the “Purchase Agreement”), (ii) that certain Investors’ Rights Agreement (the “IXX”), (iii) that certain Right of First Refusal and Co-Sale Agreement (the “ROFR and Co-Sale Agreement”), and (iv) that certain Voting Agreement (the “Voting Agreement” and together with the Purchase Agreement, the IXX and the ROFR and Co-Sale Agreement, the “Series A Financing Agreements”), each dated as of May 7, 2018, by and among In8bio, Inc. (f/k/a Innatus Therapeutics, Inc. and Incysus Therapeutics, Inc.), a Delaware corporation (the “Company”), and the respective parties named therein. Effective as of the undersigned’s acquisition of shares of the Company’s Series A Preferred Stock, par value $0.0001 per share (the “Series A Preferred Stock”) in a subsequent Closing (as defined in the Purchase Agreement), the undersigned is hereby made a party to the Purchase Agreement as a “Purchaser” thereunder and to each of the IXX, the ROFR and Co-Sale Agreement and the Voting Agreement as an “Investor” thereunder. The undersigned agrees that this Joinder Agreement may be attached to each of the Series A Financing Agreements as a counterpart signature page thereto. The undersigned (i) acknowledges receipt of a copy of each of the Series A Financing Agreements, (ii) confirms that the representations and warranties contained in Section 3 of the Purchase Agreement are true and correct as to the undersigned as of the date hereof, (iii) acknowledges the undersigned’s waiver of the provisions of Section 4 of the Purchase Agreement with respect to each subsequent Closing and (iv) confirms that the undersigned is acquiring 882,397 shares of Series A Preferred Stock at a purchase price of $1.30787 per share, or $1,154,060.56 in the aggregate, at a subsequent Closing. The address and email address to which notices may be sent to the undersigned are as follows below. Bios Fund III, LP By: /s/ Lxxxxx Xxxxx Xxxxx, Xx. Name: Lxxxxx Xxxxx Xxxxx, Xx. Title: Managing Partner Address: Email: IN8BIO, INC. Joinder Agreement

Preferred Stock Financing. August 721, 2020 The undersigned hereby agrees to become a party to (i) that certain Series A Preferred Stock Purchase Agreement, as amended (the “Purchase Agreement”), (ii) that certain Investors’ Rights Agreement (the “IXX”), (iii) that certain Right of First Refusal and Co-Sale Agreement (the “ROFR and Co-Sale Agreement”), and (iv) that certain Voting Agreement (the “Voting Agreement” and together with the Purchase Agreement, the IXX and the ROFR and Co-Sale Agreement, the “Series A Financing Agreements”), each dated as of May 7, 2018, by and among In8bio, Inc. (f/k/a Innatus Therapeutics, Inc. and Incysus Therapeutics, Inc.), a Delaware corporation (the “Company”), and the respective parties named therein. Effective as of the undersigned’s acquisition of shares of the Company’s Series A Preferred Stock, par value $0.0001 per share (the “Series A Preferred Stock”) in a subsequent Closing (as defined in the Purchase Agreement), the undersigned is hereby made a party to the Purchase Agreement as a “Purchaser” thereunder and to each of the IXX, the ROFR and Co-Sale Agreement and the Voting Agreement as an “Investor” thereunder. The undersigned agrees that this Joinder Agreement may be attached to each of the Series A Financing Agreements as a counterpart signature page thereto. The undersigned (i) acknowledges receipt of a copy of each of the Series A Financing Agreements, (ii) confirms that the representations and warranties contained in Section 3 of the Purchase Agreement are true and correct as to the undersigned as of the date hereof, (iii) acknowledges the undersigned’s waiver of the provisions of Section 4 of the Purchase Agreement with respect to each subsequent Closing and (iv) confirms that the undersigned is acquiring 882,397 471,477 shares of Series A Preferred Stock at a purchase price of $1.30787 per share, or $1,154,060.56 616,630.63 in the aggregate, at a subsequent Closing. The address and email address to which notices may be sent to the undersigned are as follows below. Bios Fund IIIIII NT, LP By: /s/ Lxxxxx Xxxxx Xxxxx, Xx. Name: Lxxxxx Xxxxx Xxxxx, Xx. Title: Managing Partner Address: Email: IN8BIOSchedule A INVESTORS Name and Address Number of Shares Held BIOS Fund II, INCLP 1,336,149 BIOS Fund II NT, LP 584,340 BIOS Fund II QP, LP 4,365,106 Valley High Limited Partnership 229,592 Cxxxxxxxx Xxxxx 23,784 Jxxx XxXxxx 151,967 Cxxxxxxxx Xxxxxxxx 125,000 Maarten de Jong 50,046 Pxxxx Xxx 11,676 Kxxxx Xxxxxx 7,784 GC&H Investments 191,196 GC&H Investments, LLC 191,196 Axxx Xxx 29,998 Bios Fund III LP 882,397 Bios Fund III NT, LP 471,477 Bios Fund III QP, LP 5,934,313 BIOS Incysus Co-Invest I, LP 2,484,957 Bxxxxxx X. Xxxxx 38,229 Cxxxxxx X. Xxxxx, Xx. Joinder Agreement38,230 Exxxx Xxxxx Yx Xx 7,650 H.X. Xxxxxxxxxx & Co., LLC 76,459 Hxxxx Xxxxx O’Xxxx 131,804 Huckleberry, LLC 19,114 Ixxxxx Xxxxx 107,343 Jxxxxx Pee 84,992 Nxxxxx Xxxxx 42,085 PCA Revocable Trust 84,108 Rxxxxx Xxxxxx Head 38,229 Rxxxxxxx Xxxxxxxxx 76,460 Sigma Investment Corporation 38,229 Timberline Holdings III, LLC 841,063 Transcend Partners Opportunity Fund LLC 8,028,321 Woodcrest Capital, Inc. 76,459 Schedule B KEY HOLDERS Wxxxxxx Xx Txxxxx Xxxxxxx Jxx Xxxxxxxxx Pxxxx Xxxxxx

Preferred Stock Financing. August 7, 2020 The undersigned hereby agrees to become a party to (i) that certain Series A Preferred Stock Purchase Agreement, as amended (the “Purchase Agreement”), (ii) that certain Investors’ Rights Agreement (the “IXX”), (iii) that certain Right of First Refusal and Co-Sale Agreement (the “ROFR and Co-Sale Agreement”), and (iv) that certain Voting Agreement (the “Voting Agreement” and together with the Purchase Agreement, the IXX and the ROFR and Co-Sale Agreement, the “Series A Financing Agreements”), each dated as of May 7, 2018, by and among In8bio, Inc. (f/k/a Innatus Therapeutics, Inc. and Incysus Therapeutics, Inc.), a Delaware corporation (the “Company”), and the respective parties named therein. Effective as of the undersigned’s acquisition of shares of the Company’s Series A Preferred Stock, par value $0.0001 per share (the “Series A Preferred Stock”) in a subsequent Closing (as defined in the Purchase Agreement), the undersigned is hereby made a party to the Purchase Agreement as a “Purchaser” thereunder and to each of the IXX, the ROFR and Co-Sale Agreement and the Voting Agreement as an “Investor” thereunder. The undersigned agrees that this Joinder Agreement may be attached to each of the Series A Financing Agreements as a counterpart signature page thereto. The undersigned (i) acknowledges receipt of a copy of each of the Series A Financing Agreements, (ii) confirms that the representations and warranties contained in Section 3 of the Purchase Agreement are true and correct as to the undersigned as of the date hereof, (iii) acknowledges the undersigned’s waiver of the provisions of Section 4 of the Purchase Agreement with respect to each subsequent Closing and (iv) confirms that the undersigned is acquiring 882,397 4,138,248 shares of Series A Preferred Stock at a purchase price of $1.30787 per share, or $1,154,060.56 5,412,290.41 in the aggregate, at a subsequent Closing. The address and email address to which notices may be sent to the undersigned are as follows below. Bios Fund IIIIII QP, LP By: /s/ Lxxxxx Xxxxx Xxxxx, Xx. Name: Lxxxxx Xxxxx Xxxxx, Xx. Title: Managing Partner Address: Email: IN8BIO, INC. Joinder Agreement

Preferred Stock Financing. August 7February 28, 2020 The undersigned hereby agrees to become a party to (i) that certain Series A Preferred Stock Purchase Agreement, as amended (the “Purchase Agreement”), (ii) that certain Investors’ Rights Agreement (the “IXX”), (iii) that certain Right of First Refusal and Co-Sale Agreement (the “ROFR and Co-Sale Agreement”), and (iv) that certain Voting Agreement (the “Voting Agreement” and together with the Purchase Agreement, the IXX and the ROFR and Co-Sale Agreement, the “Series A Financing Agreements”), each dated as of May 7, 2018, by and among In8bio, Inc. (f/k/a Innatus Therapeutics, Inc. and Incysus Therapeutics, Inc.), a Delaware corporation (the “Company”), and the respective parties named therein. Effective as of the undersigned’s acquisition of shares of the Company’s Series A Preferred Stock, par value $0.0001 per share (the “Series A Preferred Stock”) in a subsequent Closing (as defined in the Purchase Agreement), the undersigned is hereby made a party to the Purchase Agreement as a “Purchaser” thereunder and to each of the IXX, the ROFR and Co-Sale Agreement and the Voting Agreement as an “Investor” thereunder. The undersigned agrees that this Joinder Agreement may be attached to each of the Series A Financing Agreements as a counterpart signature page thereto. The undersigned (i) acknowledges receipt of a copy of each of the Series A Financing Agreements, (ii) confirms that the representations and warranties contained in Section 3 of the Purchase Agreement are true and correct as to the undersigned as of the date hereof, (iii) acknowledges the undersigned’s waiver of the provisions of Section 4 of the Purchase Agreement with respect to each subsequent Closing and (iv) confirms that the undersigned is acquiring 882,397 7,650 shares of Series A Preferred Stock at a purchase price of $1.30787 per share, or $1,154,060.56 10,005.21 in the aggregate, at a subsequent Closing. The address and email address to which notices may be sent to the undersigned are as follows below. Bios Fund III, LP By: /s/ Lxxxxx Xxxxx Xxxxx, Xx. Name: Lxxxxx Xxxxx Xxxxx, Xx. Title: Managing Partner Address: Email: IN8BIO, INC. Joinder Agreement.