When Shang­hai’s STAR board be­gan open­ing its doors to biotech, it was con­sid­ered not just a ri­val to Nas­daq but al­so the stock ex­change in Hong Kong. Those per­cep­tions may take an am­i­ca­ble turn as Chi­na ex­pands a mu­tu­al ac­cess pro­gram with the city.

The changes mean in­vestors in main­land Chi­na will be able to own Hong Kong biotech chap­ter stocks, while those in Hong Kong — a much more in­ter­na­tion­al­ly con­nect­ed group — would have ac­cess to those list­ed on STAR. In ef­fect, it turns the Shang­hai mar­ket in­to a glob­al­ly ac­ces­si­ble ex­change overnight while al­so broad­en­ing a key source of rev­enue for HKEX.

For in­de­pen­dent in­vestor Brad Lon­car, that’s a “pret­ty big deal.”

“So if you are a com­pa­ny, it opens you to a mar­ket of 100’s of mil­lions of po­ten­tial new share­hold­ers,” he wrote to End­points News.

The move was an­nounced dur­ing Hong Kong Chief Ex­ec­u­tive Car­rie Lam’s pol­i­cy ad­dress, the first she’s de­liv­ered to a leg­is­la­ture with­out ef­fec­tive op­po­si­tion. The Chi­nese gov­ern­ment, she said, has agreed to “ac­cel­er­ate the pace of the in­clu­sion of pre-prof­it biotech­nol­o­gy list­ed in Hong Kong and stocks list­ed on the Main­land Sci-Tech In­no­va­tion Board meet­ing cer­tain pre­scribed cri­te­ria” for a pro­gram that links the two ex­changes.

Chi­na has been push­ing to re­form its cap­i­tal mar­ket in a bid to at­tract for­eign in­vestors. Aside from Shang­hai, which has re­cent­ly seen vac­cine de­vel­op­er CanSi­no reap a $748 mil­lion wind­fall, Shen­zhen has al­so set up its own biotech pro­grams on ChiNext.