ValueClick Inc.. said that its board has increased its repurchase authorization by $86 million to help offset dilution caused by previously announced acquisition of a Chicago company that has now closed.

The Westlake Village online advertising company late Wednesday said that it had repurchased 3.4 million shares since Aug. 5. Boosting the authorization brings the total the company can spend to $100 million.

ValueClick earlier this month announced that it would buy Dotomi, a Chicago “intelligent display” marketing company in a deal valued at about $295 million. The company said it paid $148 million in cash and 7.1 million in shares.

“As illustrated by our recent share repurchase activity and our board’s increased share repurchase authorization, we remain confident in our ability to gain market share,” Chief Executive James Zarley said in a statement. “We are committed to offsetting the shares issued in the Dotomi transaction with continued share repurchase activity.”

The Dotomi acquisition is expected to add about $2 million in amortization expense and $1 million in stock-based compensation expense to ValueClick’s third quarter results, the company said, but that would be offset by $8.5 million in revenue expected in the month of September. ValueClick used its credit facility to pay for part of the cash portion of the deal.

John Giuliani will continue to lead Dotomi, and has joined ValueClick’s board of directors.

Shares were up 30 cents, or 2 percent, to $15.60 in midday trading on the Nasdaq.