DALLAS — A sweetened purchase offer disclosed yesterday is expected to entice 7-Eleven Inc. shareholders to turn control of the U.S. convenience store pioneer over to its largest franchisee.

Rebuffed after its initial bid, Seven-Eleven Japan Co. Ltd. said it increased its tender offer by $5 to $37.50 a share for the 27.3 percent of the company it does not already own. The news lifted the stock 4 percent to $37.36.

Analysts expect the $1.28 billion deal to go through, in part because it has management's backing this time.

Jonathan Gasthalter, a U.S.-based spokesman for Seven-Eleven Japan, said the company expects to "conduct a review of the company, its operations, management personnel, its corporate structure (and) properties" and from there will determine "how best to organize and integrate the company with the parent."

He said it was too early to say what, if any, personnel changes are in store. But he added, "Seven-Eleven Japan intends to manage this to minimize the disruption to the company's work force."

Seven-Eleven Japan made its initial, unsolicited offer of about $1.02 billion on Sept. 1. It is seeking 90 percent of the outstanding shares in the company, which began in 1927 as the Southland Ice Co. in Dallas.