Spark Therapeutics, Inc. is a company in the U.S. stock market and it is a holding in 46 U.S.-traded ETFs. ONCE has around 3.6M shares in the U.S. ETF market. The largest ETF holder of ONCE is the iShares Russell 2000 ETF (IWM), with approximately 780.76K shares. Investors may also find of interest that the ETF with the largest allocation to ONCE stock is IQ Merger Arbitrage ETF (MNA), with a portfolio weight of 5.14%. On average, U.S. ETFs allocate 0.56% of ONCE to their portfolios.
Additionally, ONCE is a favorite stock for Vanilla and Multi-factor ETFs. It is also most likely to belong to Broad-based ETFs. The best-performing ETF in the past 12 months with ONCE as a holding is the Fidelity NASDAQ Composite Index Tracking Stock (ONEQ), with a return of 16.07%.