Shareholders will receive $330 per share as part of the deal. Investors hopped on board, driving the stock up $125 per share to $322.58 as of 10:15 a.m. ET.

The deal is set to close in the third quarter, but Stamps.com has a 40-day window allowing it to consider other offers.

“With the financial and operational support of Thoma Bravo, Stamps.com can continue to innovate and pursue growth opportunities to capture the expanding e-commerce shipping market and extend our position as the leading global multi-carrier e-commerce shipping software company,” said Ken McBride, Stamps.com’s chairman and CEO.

Thoma Bravo has over $78 billion in assets under management. It has acquired more than 300 firms in the past 20 years, and its portfolio includes J.D. Power, McAfee, and network monitoring provider SolarWinds.

The leap in share prices is a turnaround for Stamps.com, which saw its stock plunge 50% in early 2019 after it pulled out of an exclusive deal with the U.S. Postal Service. Shares, at one point, fell as low as $33.

Stamps.com has nearly 723,000 monthly subscribers, mostly small businesses, enabling them to print postage labels from their workplaces.

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