Foothill Independent Bancorp on Thursday agreed to be acquired by First Community Bancorp for $238 million in stock and options.

Each of the Glendora-based Foothill shareholders will receive about $26.14 worth of First Community stock for each Foothill share, based on an initial exchange ratio of about 0.4982 share of First Community for each Foothill share.

The ratio is tied to First Community’s average stock price during the 15 days before the agreement was signed, which the Rancho Santa Fe-based bank holding company said was $52.47 per share. The final value of the deal will vary according to First Community’s stock price move over a final 15-day period, ending two trading days prior to the closing, which is expected to be in the second quarter of 2006.

After the acquisition closes, Foothill will be merged into Pacific Western National Bank, a Los Angeles-based subsidiary of First Community.

First Community, with $3.1 billion in loans and other assets and 41 branches, said the acquisition would strengthen its position in the fast-growing market of southern California. Foothill, the parent of Foothill Independent Bank, had $794 million in assets and 12 branches in Los Angeles, Riverside and San Bernardino counties as of Sept. 30.

Shares of Foothill were up 1.9 percent to $25.10 in early-afternoon trading on Thursday.