...- Jane Street Group LLC, which previously specialized in ETF market making, has substantively diversified its activities over the last few years. It has developed into a leading, highly profitable market maker and liquidity provider for multiple asset classes, including equities, options, and fixed income across the globe. - The company's focus on expansion and growth brings risks, but we think they're offset, to some extent, by its strong capital base, its impressive retained earnings, and the recent improvements in its funding profile. - We affirmed our '##' ratings on Jane Street Group and revised the outlook on our issuer credit rating to positive from stable. - The positive outlook reflects the possibility that we could raise the ratings in the next 12-18 months if the company sustains benefits from its enhanced scale and increased diversification, while also maintaining the improvements in its funding profile and its strong capital position....