X0609 4 2026-03-16 1 0001898474 Signing Day Sports, Inc. SGN 0002020963 Smith Craig Steven C/O SIGNING DAY SPORTS, INC 8355 EAST HARTFORD RD., SUITE 100 SCOTTSDALE AZ 85255 0 1 0 0 COO and Secretary 0 Common Stock 2026-03-16 4 D 0 28775 D 0 D Stock Option (right to buy) 120.00 2026-03-16 4 D 0 1042 D 2033-05-03 Common Stock 1042 0 D Pursuant to the Business Combination Agreement, dated as of May 27, 2025, by and among Signing Day Sports, Inc., a Delaware corporation (the "Registrant"), One Blockchain LLC, a Delaware limited liability company, BlockchAIn Digital Infrastructure, Inc., a Delaware corporation ("BlockchAIn"), BCDI Merger Sub I Inc., a Delaware corporation, and BCDI Merger Sub II LLC, a Delaware limited liability company, as amended (the "Business Combination Agreement"), on the date of the closing (the "Closing") of the transactions contemplated by the Business Combination Agreement, or March 16, 2026 (the "Closing Date"), the reporting person received 0.09334 common shares of BlockchAIn for every share of common stock of the Registrant held by the reporting person, subject to rounding adjustments, having a market value of $4.60 per share based on the first reported sale price of the common stock of BlockchAIn on the NYSE American LLC after the Closing, which was reported on March 17, 2026. Pursuant to the terms of the Business Combination Agreement, on the Closing Date, the reporting person's option, which provided for vesting as to 261 shares on November 16, 2024 and as to 1/36 of the remaining unvested shares in each of the following 36 months, immediately became fully vested, was assumed by BlockchAIn, and was automatically converted into an option to purchase 98 common shares of BlockchAIn exercisable for $1,285.62 per share. /s/ Craig Smith 2026-03-18