It's hard to bar hop on the Pittsburgh night scene without giving money to Thomas Jayson. Few entrepreneurs have had more of an impact on local nightlife than the reclusive Carnegie entrepreneur.

The owner of Touch, the Strip District nightclub where eight people were shot early Monday, Mr. Jayson has had a financial stake in more than a dozen restaurants, bars, lounges and nightclubs from the Strip and South Side to Bridgeville.

The roster of his current and former holdings includes Touch, Chauncy's, Rock Jungle, Donzi's, Cruiser's, Sports Rock Cafe, Light, Bongo's, Mirage, Matrix, Tequila Willie's, Ref's and Callahan's.

Since the mid-1990s, he's been the defendant in dozens of cases involving lawsuits against him and his holdings, the defendant under alternative names in a dozen more, and listed as "plaintiff" or "tax payer" in additional legal matters.

Mr. Jayson also has been involved in some of the city's most high-profile nuisance bar cases in recent years.

A federal probe described more than 80 incidents in a 16-month period in which Station Square security or Pittsburgh police were called to Chauncy's. After Mr. Jayson sold the club, its manager was arrested for large-scale heroin dealing and money laundering on the premises.

Rock Jungle, another Station Square venue owned by Mr. Jayson and licensed to hold more than 1,300 people, was the scene of a 2003 melee described as a youth riot and was raided several times for under-age drinking before it ultimately closed.

The former Donzi's, on the floating Strip District Boardwalk complex, was the site of nuisance complaints.

Some of Mr. Jayson's operations, however, have no record of public disturbances, and even his venues with troubled histories have remained popular on the local night scene.