The security software vendor Entrust Inc. announced a $114 million agreement Monday to sell itself to the private-equity firm Thoma Bravo LLC.

"After an extensive review of our strategic alternatives, Entrust's board of directors has determined that this transaction provides for the best value to shareholders," Michael McGrath, Entrust's chairman, said in a press release.

Entrust, of Dallas, said that Thoma Bravo, of Chicago and San Francisco, agreed to pay $1.85 per share in cash. Entrust, a developer of products and services for digital identities, said the price was a premium of 22.4% over Entrust's average closing share price of $1.51 during the 30 previous trading days. The stock closed at $1.67 Thursday.

A spokesman said the deal is likely to close by the middle of the third quarter. Entrust said in its press release that the agreement permits it to seek alternative proposals during the next 30 days.

There is no financing condition on the transaction, and Thoma Bravo has received equity and debt commitments for the deal, Entrust said.

Thoma Bravo manages approximately $2.5 billion of equity capital. In the past its portfolio has included other financial technology companies, such as the check imaging vendor VectorSGI of Addison, Tex., which was acquired in November 2004 by the company now known as Metavante Technologies Inc.