Analyst Update: Peabody Energy, Ambarella, aTyr Pharma

Analysts are weighing in on coal concern Peabody Energy Corporation (NYSE:BTU), semiconductor specialist Ambarella Inc (NASDAQ:AMBA), and drugmaker aTyr Pharma Inc (NASDAQ:LIFE). Here's a quick roundup of today's brokerage notes on BTU, AMBA, and LIFE.

• BTU has earned a dreary spot on the Big Board, after Goldman Sachs initiated coverage on the stock with a "sell" rating and a $2 price target, citing concerns over domestic thermal coal demand. At last check, the security was down 6.2% at $3.16, and fresh off a record low of $3.15. Today's negative price action just echoes the withstanding trajectory of a security that's surrendered 80% of its value year-over-year. Peabody Energy Corporation could encounter a fresh wave of selling pressure, too, should any analysts follow in Goldman Sachs' footsteps. Currently, seven out of 17 brokerage firms maintain a "buy" or better rating on the equity, while the average 12-month price target of $7.10 stands at a 125% premium to BTU's present perch.


• Ahead of AMBA's turn in the earnings confessional tomorrow night, Deutsche Bank raised its price target on the stock to $80 from $64. The bullish brokerage note has sent the shares soaring to yet another record high; this time, with AMBA topping out at $93.86. Longer term, the stock has added 85% in 2015, and was last seen lingering near $93.73. In the options pits, speculators have shown an increasing preference for puts over calls among options set to expire in three months or less. Specifically, Ambarella Inc's Schaeffer's put/call open interest ratio (SOIR) has jumped to 1.10 from its May 18 reading of 0.94, and now ranks in the 66th percentile of its annual range.


• Wall Street newcomer LIFE received a bevy of bullish brokerage notes, and has moved 2.1% higher to $23.36 as a result. Both BMO and William Blair, for example, initiated coverage with an "outperform" rating and a $42 price target. Elsewhere, J.P. Morgan Securities started the stock with an "overweight" recommendation and a $44 target price, while Citigroup began coverage with a "buy" suggestion and a $32 price target. Since going public on May 7, aTyr Pharma Inc has tacked on more than 75%, and topped out at a post-IPO peak of $27.82 on May 21.