NEW YORK (TheStreet) -- Shares of AVG Technologies  (AVG) are soaring 31.56% to $24.72 on heavy trading volume early Thursday afternoon after agreeing to be purchased by rival security software provider Avast Software for $1.3 billion in cash.

Prague, Czech Republic-based Avast has offered to buy all of AVG's outstanding ordinary shares for $25 per share in cash, representing a 33% premium to AVG's Wednesday closing price.

"We are in a rapidly changing industry, and this acquisition gives us the breadth and technological depth to be the security provider of choice for our current and future customers," Avast CEO Vince Steckler said in a statement.

The combined company will have a network of more than 400 million endpoints, of which 160 million will be mobile, that act as de facto sensors to provide information about malware to detect and neutralize new threats, according to a statement by AVG.

About 13.01 million shares of AVG have been traded so far today, well above its average trading volume of roughly 297,126 shares per day.

Separately, TheStreet Ratings team rates the stock as a "hold" with a ratings score of C+.

AVG Technologies' strengths such as its revenue growth, expanding profit margins and notable return on equity are countered by weaknesses including generally higher debt management risk, weak operating cash flow and a generally disappointing performance in the stock itself.

You can view the full analysis from the report here: AVG

TheStreet Ratings objectively rated this stock according to its "risk-adjusted" total return prospect over a 12-month investment horizon. Not based on the news in any given day, the rating may differ from Jim Cramer's view or that of this article's author.