Allianz SE is exploring a plan to take Euler Hermes Group private, buying the shares it doesn’t already own in the French trade-credit insurer, according to people familiar with the matter. Euler Hermes stock gained the most in more than four years.

The German firm, which already owns about 63 percent of Euler, is speaking to advisers about acquiring the remaining stake, which has a market value of about 1.5 billion euros ($1.7 billion), the people said, asking not to be identified because the deliberations are private. Discussions are ongoing and Allianz regularly reviews the holding, but no final decision has been made, they said.

Allianz Chief Executive Officer Oliver Baete missed out on an opportunity to deploy a 3 billion-euro war chest for acquisitions as a deadline for deals passed in February and the insurer was forced to return the money to shareholders through the first-ever buyback in the insurer’s 127-year history. Baete, however, has said the company could still finance a takeover.

Any transaction will add to the $61.1 billion in deals targeting insurance companies announced over the past 12 months, according to data compiled by Bloomberg. Euler Hermes offers trade credit insurance, a type of policy offered to companies wishing to protect themselves from losses due to customer default. Its shares have risen 18 percent so far this year, giving the Paris-based company a market value of about 4.2 billion euros.

A spokesman for Allianz declined to comment, and a spokesman for Euler Hermes said the company doesn’t comment on market rumors or speculation.

Euler Hermes rose as much as 7.9 percent in Paris and was up 2.3 percent at 99.15 euros at 10:15 a.m. Allianz rose 0.8 percent to 171.85 euros in Frankfurt.

Share Buyback

Increasing its exposure to credit insurance should help Allianz reduce its overall combined ratio and enhance profitability, RBC Capital Markets analyst Paul De’Ath, who has an outperform rating on Allianz shares, wrote in a note to clients. “We expect that this could be financed internally at Allianz whilst also maintaining the 3 billion-euro share buyback for 2017,” he said.

Allianz had been cautious about deals since the 2001 purchase of Dresdner Bank. Allianz ended that relationship in an emergency sale in 2008, weeks before the Lehman Brothers debacle. Its last major acquisition was a decade ago, when it bought the remaining shares of Assurances Generales de France.

Euler Hermes is the world’s biggest trade-credit insurer with a share of about a third of the global market, where premiums rose 5 percent in 2015 to 6.4 billion euros, according to the latest annual report by the International Credit Insurance & Surety Association.