May 9 (Reuters) - Ideagen Plc agreed to a takeover by London-based private equity firm Hg Pooled Management in an all-cash deal, valuing the British software firm at 1.09 billion pounds ($1.34 billion), the companies said on Monday.

Hg said shareholders of Ideagen, whose software helps companies comply with regulation and manage risk, will receive 350 pence per share, representing a premium of about 52% to its closing price on April 11.

Shares in Ideagen jumped 46% to 355 pence on Monday, above Hg's offer price, indicating that investors are expecting a counter bid from French rival suitor Astorg.

Ideagen, which operates in the regulatory and compliance software sector serving more than 8,000 customers including Heineken and British Airways, has seen a flurry of takeover interest since early April.

London-based private equity firm Cinven said on April 14 it was in talks for a possible offer for Ideagen, but dropped its pursuit last week.

Ideagen, in a separate statement, said it remained in talks with fund management company Astorg, which has been given access to due diligence.

The London-listed company, whose board plans to unanimously recommend the Hg deal to shareholders, said it believed the offer from Rainforest Bidco, a company indirectly controlled by funds managed by Hg, "represents value for shareholders".

($1 = 0.8147 pounds) (Reporting by Muhammed Husain and Yadarisa Shabong in Bengaluru; Editing by Sherry Jacob-Phillips)