UPDATE 1-Hastor family says not seeking a hostile takeover of Grammer

* Hastor family owns just over 20 pct of Grammer

* Demands EGM to replace nearly half of supervisory board

* Says Grammer has not addressed margin erosion (Adds further Hastor comments, background)

FRANKFURT, Feb 2 (Reuters) - Bosnia’s Hastor family said its demand to replace nearly half of German automotive interiors maker Grammer’s supervisory board should not be construed as an aggressive move to gain control of the company.

The Hastor family, which controls automotive supplier Prevent, has built a stake of just over 20 percent in Grammer but has so far not made clear its intentions.

The family’s investment vehicle Cascade International Investment GmbH said in a statement on Thursday that Grammer’s leadership had not sufficiently addressed eroding profit margins, renewing its call for an extraordinary general meeting.

“Intensified supervision in the face of the aforementioned deficits should not be misunderstood as a hostile takeover,” the Cascade statement said.

Grammer’s operating margin shrank to 3.0 percent in 2015 from 4.2 percent in 2014 and 4.6 percent in 2013 as the group invested to expand production at its automotive division, which among other makes head rests and centre consoles for cars.

Grammer earlier this week rebuffed the Hastor family’s push to replace five of the company’s 12 supervisory board members.

Cascade holds about half of the Hastor family’s stake in Grammer while the other half is owned by Halog, another investment vehicle. Both are controlled by Damir and Kenan Hastor, the sons of Prevent founder Nijaz Hastor who are listed by Forbes as the richest Bosnians. Prevent was in a dispute with Volkswagen last year.

Grammer counts Germany’s big automakers among its major customers, with Volkswagen alone accounting for 35 percent of sales at its automotive business. (Reporting by Maria Sheahan; Editing by Christoph Steitz and Jane Merriman)