* Biotest welcomes talks with Chinese suitor
* Other potential bidders had approached Biotest
* Biotest in drive to double output capacity
* No premium offered for non-voting shares (Adds CEO comments, advisor names)
By Ludwig Burger and Patricia Weiss
FRANKFURT, March 30 (Reuters) - Chinese investor Creat Group Corp has offered to buy German blood plasma products maker Biotest for about 1.2 billion euros ($1.3 billion) including debt following its purchase last year of British peer Bio Products Laboratory.
"The Board of Management and Supervisory Board welcome the discussions," Biotest said, adding the suitor would back an ongoing investment drive to more than double output capacity by 2022.
Biotest Chief Executive Bernhard Ehmer told a news conference on Thursday that Creat had not been the only potential bidder to approach Biotest about a deal but it chose to talk to Creat because its proposal was "thought through".
No negotiations with other parties were taking place at present, a person close to the matter said.
Biotest said Creat had proposed a purchase price of 28.50 euros per ordinary share, a 43 percent premium over Wednesday's closing price.
However owners of preference shares without voting rights and therefore unable to block or approve any deal would be offered only 19 euros apiece, a slight discount to Wednesday's 19.02 euro close.
The preference shares slipped almost 5 percent to 18.08 euros at 1445 GMT, while the ordinary shares jumped 25 percent to 25 euros.
OGEL, the investment vehicle of late company founder Hans Schleussner's family, holds slightly more than half of Biotest's ordinary shares with voting rights.
Biotest, whose products are used to treat blood coagulation disorders, auto-immune diseases and immune deficiencies, said the potential deal was still subject to final negotiations and an agreement with majority shareholder OGEL.
Creat also holds a stake in Biotest peer Shanghai RAAS Blood Products, which competes with groups such as CSL Behring, Grifols and Shire unit Baxalta.
Germany and China have been involved in an increasingly public dispute about access to each others' markets, with China complaining about unfair scrutiny of its acquisition targets in Germany, and Germany wanting a more level playing-field for its firms in the world's second-largest economy.
Due to the talks, Biotest said it postponed its annual shareholder meeting, initially planned for May 10, to a later date, which was yet to be announced.
Biotest's share capital is split evenly between ordinary and preference shares, with latter share class being completely in free-float ownership.
Creat agreed in May last year to acquire British biotech firm Bio Products Laboratories (BPL) from Bain Capital for 820 million pounds ($1.02 billion).
Biotest, which is being advised by Credit Suisse, suffered a setback last week when its partner Immunogen decided to cease work with Biotest on bringing an experimental blood cancer treatment to the U.S. market.
Bank of America is advising Creat. ($1 = 0.9313 euros) (Additional reporting by Arno Schuetze; Editing by Keith Weir)