Analysts’ downgrades for Friday, August 11th:

National General Holdings Corp (NASDAQ:NGHC) was downgraded by analysts at Zacks Investment Research from a buy rating to a hold rating. According to Zacks, “National General Holdings Corp. is a specialty personal lines insurance holding company. The Company, through its subsidiaries, provides personal and commercial automobile insurance, recreational vehicle and motorcycle insurance, supplemental health insurance products and other niche insurance products. It operates in two segments, Property and Casualty and Accident and Health. The Property and Casualty segment offers standard and preferred automobile and sub-standard automobile insurance policies; Recreational vehicle insurance policies; commercial automobile insurance policies; and motorcycle insurance policies for various types of motorcycles, as well as golf carts and all-terrain vehicles. The Accident and Health segment provides accident and non-major medical health insurance products. National General Holdings Corp. is headquartered in New York. “

Northern Oil & Gas (AMEX:NOG) was downgraded by analysts at Zacks Investment Research from a hold rating to a sell rating. According to Zacks, “NORTHRN OIL & GAS, Inc. is an exploration and production company based in Wayzata, Minnesota. Northern Oil’s core area of focus is the Williston Basin, specifically the Mountrail County, North Dakota area Bakken Play. Northern Oil’s secondary objective is conventional, 3D driven, oil and gas exploration and development throughout the Rocky Mountain region. “

Nevro Corp. (NYSE:NVRO) was downgraded by analysts at Zacks Investment Research from a buy rating to a hold rating. According to Zacks, “Nevro Corp. is a medical device company. It engages in developing and commercializing a neuromodulation platform for the treatment of chronic pain. The Company provides pain relief to the customers suffering from low back pain and types of chronic pains. Nevro has developed and commercialized the Senza (R) spinal cord stimulation (SCS) system for the treatment of chronic pain. Senza, HF10, Nevro and the Nevro logo are trademarks of the company. Nevro Corp. is headquartered in Menlo Park, California. “

NxStage Medical (NASDAQ:NXTM) was downgraded by analysts at Zacks Investment Research from a buy rating to a hold rating. According to Zacks, “NxStage Medical, Inc. is a medical device company, headquartered in Lawrence, Massachusetts, USA, that develops, manufactures and markets innovative systems for the treatment of end-stage renal disease, or ESRD, and acute kidney failure. “

Olympus Corp. (OTCMKTS:OCPNY) was downgraded by analysts at Zacks Investment Research from a buy rating to a hold rating. According to Zacks, “OLYMPUS CORPORATION is a Japan-based company. The Company is engaged in the manufacturing and selling of precision machineries and instruments. The businesses of the Company include Imaging System Business, Medical Systems Business, Life Science Business, Information and Communication Business, and Others Business. Olympus has always been a company that makes people’s dreams come true through innovative products. Olympus cameras have always been at the leading edge of innovation. “

Oncolytics Biotech (NASDAQ:ONCYF) was downgraded by analysts at Zacks Investment Research from a hold rating to a sell rating. According to Zacks, “Oncolytics Biotech, Inc. focuses on the discovery and development of pharmaceutical products for the treatment of a wide variety of human and companion pet cancers. The Company was formed to explore the oncolytic capability of the reovirus, a virus that preferentially replicates in cells with an activated Ras pathway, one of the most common family of genetic defects leading to cancer. “

Ply Gem Holdings (NYSE:PGEM) was downgraded by analysts at Zacks Investment Research from a hold rating to a sell rating. According to Zacks, “Ply Gem Holdings Inc. is engaged in manufacturing and selling exterior building products primarily in the United States and Canada. Its business segment consists of: Siding, Fencing, and Stone and Windows and Doors. The Company offers vinyl siding, designer accents, cellular PVC trim, vinyl fencing, vinyl and composite railing, stone veneer and vinyl windows and doors. Its brand name include Variform(R), Napco(R), Mastic Home Exteriors(R), Cellwood(R), Kroy and Kroy Express(R), Ply Gem Stone(R), Georgia-Pacific and Durabuilt (R), Ply Gem Windows(R), Great Lakes Window(R). The company serves residential and commercial construction, manufactured housing, professional remodelling and renovation markets. Ply Gem Holdings Inc. is headquartered in Cary, North Carolina. “

Planet Payment (NASDAQ:PLPM) was downgraded by analysts at Zacks Investment Research from a hold rating to a sell rating. According to Zacks, “Planet Payment, Inc. is a provider of international payment processing and multi-currency processing services. It operates in two segments: processing solutions and merchant solutions. The company’s processing solutions include secure payment processing, multi-currency authorization and capture processing, clearing and settlement, acquirer reconciliation and reporting, POS, banking ATMs services and risk management services. Its Merchant solutions comprises of multi-currency payment solutions; online payment solutions designed for e-commerce, MICROS payment gateway, POS solutions, payments reporting, data analytics services and global merchant solutions, as well as fraud and security services. It offers its services primarily to Asia Pacific region, North America, Latin America, the Middle East, Africa, and Europe. Planet Payment, Inc. is headquartered in Long Beach, New York. “

PRA Health Sciences (NASDAQ:PRAH) was downgraded by analysts at Zacks Investment Research from a hold rating to a sell rating. According to Zacks, “PRA Health Sciences, Inc. operates as a global contract research organizations providing outsourced clinical development services to the biotechnology and pharmaceutical industries. It offers therapeutic services in the areas of cardio-metabolic, biosimilars, infectious diseases, immunology, neurology and psychiatry, oncology and hematology, rare diseases, and respiratory needs. The Company engages in bioanalytical laboratory, clinical pharmacology, clinical development, strategic solutions, post marketing research, clinical informatics, clinical diagnostics, and safety and risk management activities. PRA Health Sciences, Inc. is based in Raleigh, North Carolina. “

Primerica (NYSE:PRI) was downgraded by analysts at Zacks Investment Research from a hold rating to a sell rating. According to Zacks, “Primerica, Inc. provides financial products and services. It assists its clients in meeting their needs for term life insurance, which it underwrites, and mutual funds, variable annuities and other financial products, which it distributes primarily on behalf of third parties. The Company’s mission is to serve middle income families by helping them make informed financial decisions and providing them with a strategy and means to gain financial independence. The Company’s sales representatives use its proprietary financial needs analysis, or FNA, tool and an educational approach to demonstrate how its products can assist clients to provide financial protection for their families, save for their retirement and manage their debt. The Company’s clients are generally middle income consumers. Primerica also provides an entrepreneurial business opportunity for individuals to distribute its financial products. The Company is based in Duluth, Georgia. “

Primoris Services Corporation (NASDAQ:PRIM) was downgraded by analysts at Zacks Investment Research from a buy rating to a hold rating. According to Zacks, “Primoris Services Corporation, through various subsidiaries, operates as one of the largest specialty contractors and infrastructure companies in the United States. The Company provides a wide range of construction, fabrication, maintenance, replacement, water and wastewater, and engineering services to major public utilities, petrochemical companies, energy companies, municipalities, and other customers. It operates through three segments: East Construction Services; West Construction Services; and Engineering. Primoris Services Corporation is headquartered in Dallas, Texas. “

Ryman Hospitality Properties (NYSE:RHP) was downgraded by analysts at Zacks Investment Research from a hold rating to a sell rating. According to Zacks, “Ryman Hospitality Properties, Inc. is a Real Estate Investment Trust specializing in group-oriented, destination hotel assets in urban and resort markets. The Company also operates a number of media and entertainment assets that includes the Grand Ole Opry, the Ryman Auditorium and WSM-AM. Ryman Hospitality Properties, Inc. is headquartered in Nashville, Tennessee. “

Red Rock Resorts (NASDAQ:RRR) was downgraded by analysts at Zacks Investment Research from a hold rating to a strong sell rating. According to Zacks, “Red Rock Resorts manage and own an indirect equity interest in Station Casinos LLC. Station is the provider of gaming and entertainment primarily in Las Vegas, Nevada. Red Rock Resorts is based in LAS VEGAS, United States. “

ROTORK (NASDAQ:RTOXY) was downgraded by analysts at Zacks Investment Research from a hold rating to a sell rating. According to Zacks, “Rotork plc is an actuator manufacturer and flow control company. Its operating segment consists of Process Control, Electric, Fluid Systems and Gears. The company primarily serves power generation, oil and gas, water and sewage, marine, mining and other industries. Rotork plc is headquartered in Bath, the United Kingdom. “

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