ARCA biopharma, Inc. is a company in the U.S. stock market and it is a holding in 6 U.S.-traded ETFs. ABIO has around 126.7K shares in the U.S. ETF market. The largest ETF holder of ABIO is the Vanguard Total Stock Market ETF (VTI), with approximately 69.28K shares. Investors may also find of interest that the ETF with the largest allocation to ABIO stock is iShares Micro-Cap ETF (IWC), with a portfolio weight of 0.01%. On average, U.S. ETFs allocate 0.00% of ABIO to their portfolios.