(Corrects to remove reference to South Korea in lede and headline in reference to Biogen)
* Biogen to receive shares valued at $2.02 billion-BioLogics
* Matter has bearing in regulatory scrutiny into BioLogics-sources
* BioLogics shares fell sharply in May after regulatory scrutiny
By Joyce Lee
SEOUL, June 29 (Reuters) - Biogen said it had exercised its option to purchase additional shares of biopharma developer Samsung Bioepis Co Ltd, a joint venture established in 2012 by Samsung BioLogics Co Ltd and Biogen.
The move announced by the U.S. biotech company late on Thursday is expected to be taken into consideration by South Korean regulators who are investigating Samsung BioLogics' bookkeeping in 2015, sources said.
Samsung BioLogics shares plunged in early May after the financial watchdog said it had breached accounting rules concerning its valuation of subsidiary Samsung Bioepis in 2015.
Samsung BioLogics' valuation of Samsung Bioepis jumped 18 times to about $4.5 billion in 2015 after it switched to valuing the unlisted firm at fair market value instead of book value, a result of it being treated as an affiliate instead of a unit.
BioLogics has denied any wrongdoing and said the change was necessary to reflect different accounting standards in the event its partner exercised its call option.
The matter is now being examined by a body within the Financial Services Commission (FSC), South Korea's top financial regulator.
Biogen's call option exercise will be one of the matters considered when the FSC decides whether BioLogics' accounting was sound, regulatory sources previously told Reuters.
Samsung BioLogics shares rose 4.8 percent in early Friday trade after the news.
Drug contract manufacturer Samsung BioLogics said in a separate regulatory filing on Friday that the additional shares Biogen would receive by exercising its call option were valued at about 2.26 trillion won ($2 billion), and Biogen would pay Samsung BioLogics 748.6 billion won to exercise its call option.
With the call option exercised, Biogen is expected to raise its stake in Samsung Bioepis from 5.4 percent at the end of 2017 to 50 percent minus one share.
$1 = 1,120.2000 won Reporting by Joyce Lee; Editing by Stephen Coates