Editor's Note: Any reference to TheStreet Ratings and its underlying recommendation does not reflect the opinion of TheStreet, Inc. or any of its contributors including Jim Cramer. Two out of the three major indices are trading up today with the Dow Jones Industrial Average ( ^DJI) trading up 13 points (0.1%) at 17,609 as of Tuesday, June 30, 2015, 12:55 PM ET. The NYSE advances/declines ratio sits at 1,652 issues advancing vs. 1,385 declining with 154 unchanged. The Health Care sector currently sits up 1.3% versus the S&P 500, which is unchanged. Top gainers within the sector include Intrexon ( XON), up 4.3%, Opko Health ( OPK), up 4.1%, Biomarin Pharmaceutical ( BMRN), up 2.1%, Illumina ( ILMN), up 1.7% and Gilead ( GILD), up 1.4%. On the negative front, top decliners within the sector include Cigna ( CI), down 1.2%, GlaxoSmithKline ( GSK), down 1.1%, Fresenius Medical Care AG & Co. KGaA ( FMS), down 1.1%, Teva Pharmaceutical Industries ( TEVA), down 0.9% and Pfizer ( PFE), down 0.6%. TheStreet would like to highlight 3 stocks pushing the sector higher today: 3. bluebird bio ( BLUE) is one of the companies pushing the Health Care sector higher today. As of noon trading, bluebird bio is up $7.86 (4.9%) to $167.13 on average volume. Thus far, 518,105 shares of bluebird bio exchanged hands as compared to its average daily volume of 869,900 shares. The stock has ranged in price between $161.50-$167.24 after having opened the day at $161.68 as compared to the previous trading day's close of $159.27. EXCLUSIVE OFFER: See inside Jim Cramer's multi-million dollar charitable trust portfolio to see the stocks he thinks could be potential winners. Click here to see his holdings for 14-days FREE. bluebird bio, Inc., a clinical-stage biotechnology company, focuses on developing transformative gene therapies for severe genetic and rare diseases. Bluebird bio has a market cap of $5.4 billion and is part of the drugs industry. Shares are up 80.6% year-to-date as of the close of trading on Monday. Currently there are 9 analysts who rate bluebird bio a buy, no analysts rate it a sell, and none rate it a hold. TheStreet Ratings rates bluebird bio as a sell. The company's weaknesses can be seen in multiple areas, such as its feeble growth in its earnings per share, deteriorating net income and weak operating cash flow. Get the full bluebird bio Ratings Report now. EXCLUSIVE OFFER: See inside Jim Cramer's multi-million dollar charitable trust portfolio to see the stocks he thinks could be potential winners. Click here to see his holdings for 14-days FREE.