What is the relationship between Premier Oil and Public Limited Company in the context of the input sentence. Choose an answer from: product/material produced; manufacturer; distributed by; industry; position held; original broadcaster; owned by; founded by; distribution format; headquarters location; stock exchange; currency; parent organization; chief executive officer; director/manager; owner of; operator; member of; employer; chairperson; platform; subsidiary; legal form; publisher; developer; brand; business division; location of formation; creator.

FTSE 250 - Risers Cobham (Amsterdam: CH6.AS - news ) (COB) 278.20p +5.98% Enterprise Inns (ETI) 119.30p +4.01% Phoenix Group Holdings (DI (KSE: 003160.KS - news ) ) (PHNX) 896.00p +2.99% Bovis Homes Group (BVS) 1,180.00p +2.43% Ted Baker (Other OTC: TBAKF - news ) (TED) 3,274.00p +2.38% UDG Healthcare Public Limited Company (UDG) 527.50p +2.23% Aldermore Group (LSE: ALD.L - news ) (ALD) 264.00p +2.21% Supergroup (Stuttgart: 49S.SG - news ) (SGP) 1,476.00p +1.93% Berkeley Group Holdings (The) (BKG) 3,453.00p +1.83% Dairy Crest Group (DCG) 599.50p +1.78% FTSE 250 - Fallers Tullow Oil (TLW) 222.20p -8.67% Lonmin (LMI) 40.91p -7.88% Premier Oil (PMO) 116.80p -7.81% Ophir Energy (Other OTC: OPGYF - news ) (OPHR) 108.30p -5.66% Just Eat (Other OTC: JSTLF - news ) (JE.)

Answer: legal_form