Both companies are involved in the amusement industry (Sega with arcade and home video games, Sammy with pachinko machines).

In 1969, Sega Enterprises was acquired by U.S. conglomerate Gulf and Western Industries (which also owned the famed movie studio Paramount Pictures around this time).

During this year, Sega also launched the R-360, the world's first amusement arcade cabinet could rotate 360 degrees in all directions.

In 2001, Sega discontinued the Dreamcast and withdrew from the console hardware industry to become a third-party video game developer and publisher.

By 2000, Sammy Corporation was listed in the Tokyo Stock Exchange's 1st section, indicating it as a "large company".

[5] Outside of Pachinko and Pachislot industry, Sammy Corporation was also involved in the video game industry as a publisher for fighting games such as the Guilty Gear series (developed by Arc System Works), The Rumble Fish series (developed by Dimps) and Survival Arts.

[7] According to the first Sega Sammy Annual Report, the merger happened due to the companies facing financial difficulties.

According to chairman Hajime Satomi, Sega had been in the red for nearly 10 years[8] and lacked a clear financial base.

[18][19] On January 29, 2021, Sega Sammy announced that it would restructure and split its corporate functions for their businesses which occurred at the beginning of the 2022 fiscal year.

[22] Rovio rejected an earlier acquisition bid from Israeli mobile company Playtika for $800 million.

[24] In November 2023, Sega Sammy Creation announced that it would acquire sports betting company, GAN Limited, for the price of $1.97 per share pending regulatory approval.

[27] In July 2024, Sega Sammy announced it would acquire Dutch online gambling platform Stakelogic for $141 million, pending regulatory approval with the transaction set to close by the 2026 fiscal year.

[28] Sega Sammy's business consists of three segments, which covers entertainment contents (including video games, animation and toys), pachinko & pachislot and casino & resort.

[29] These are the companies and subsidiaries affiliated with Sega Sammy Group's pachislot and pachinko machine business.