Research Analysts’ downgrades for Friday, September 1st:

Ambarella (NASDAQ:AMBA) was downgraded by analysts at Roth Capital from a buy rating to a neutral rating.

America First Multifamily Investors, L.P. (NASDAQ:ATAX) was downgraded by analysts at Oppenheimer Holdings, Inc. from an outperform rating to a market perform rating.

BHP Billiton Limited (NYSE:BHP) was downgraded by analysts at Raymond James Financial, Inc. from a market perform rating to an underperform rating.

Deutsche Boerse Ag (NASDAQ:DBOEY) was downgraded by analysts at Morgan Stanley from an overweight rating to an equal rating.

Dixons Carphone (OTCMKTS:DSITF) was downgraded by analysts at Investec from a buy rating to a hold rating.

GKN plc (NASDAQ:GKNLY) was downgraded by analysts at HSBC Holdings plc from a hold rating to a reduce rating.

J D Wetherspoon PLC (NASDAQ:JDWPY) was downgraded by analysts at HSBC Holdings plc from a buy rating to a hold rating.

Rice Energy (NYSE:RICE) was downgraded by analysts at US Capital Advisors from a buy rating to a hold rating.

TDK Corp. (OTCMKTS:TTDKY) was downgraded by analysts at Zacks Investment Research from a hold rating to a sell rating. According to Zacks, “TDK Corp. has a portfolio of technologies originally developed for its businesses involving electronic materials, components and devices, semiconductor, recording media and data storage devices. Its technical leadership includes materials research and development for dielectric, organic and semiconductor materials, process technologies for thick and thin film, metal, semiconductors and integration technologies. TDK technologies can be found in multimedia, video, television, personal computers, mobile communications, and semiconductors. (PRESS RELEASE) “

Vipshop Holdings Limited (NYSE:VIPS) was downgraded by analysts at Zacks Investment Research from a buy rating to a hold rating. According to Zacks, “Vipshop Holdings Ltd. is an online discount retailer for brands. The Company offers branded products to consumers in China through flash sales on its vipshop.com website. It offers a wide selection of various famous branded discount products including apparel for women, men and children, fashion goods, cosmetics, home goods and other lifestyle products, through its website. Vipshop Holdings Ltd. is headquartered in Guangzhou. “

Vantiv (NYSE:VNTV) was downgraded by analysts at Zacks Investment Research from a buy rating to a hold rating. According to Zacks, “Vantiv, Inc. is an integrated payment processor engaged in providing advanced technology solutions for businesses and financial institutions. The Company operates in two segments: Merchant Services and Financial Institution Services. Vantiv offers acquiring and processing transactions, value-added services, merchant services and reporting for electronic payment transactions. It also provides card issuer processing, payment network processing, fraud protection, card production, prepaid program management, automated teller machine driving, network gateway and switching services. Vantiv, Inc. is headquartered in Cincinnati, Ohio. “

Western Alliance Bancorporation (NYSE:WAL) was downgraded by analysts at Zacks Investment Research from a buy rating to a hold rating. According to Zacks, “Western Alliance Bancorporation is the parent company of BankWest of Nevada, Alliance Bank of Arizona, Torrey Pines Bank, Miller/Russell & Associates, and Premier Trust. These dynamic companies provide a broad array of banking, leasing, trust, investment, and mortgage services to clients in Nevada, Arizona and California. Staffed with experienced financial professionals, these organizations deliver a broader product array and larger credit capacity than community banks, yet are empowered to be more responsive to customers’ needs than larger institutions. “

Willbros Group (NYSE:WG) was downgraded by analysts at Zacks Investment Research from a buy rating to a hold rating. According to Zacks, “Willbros Group, Inc. is an independent contractor serving the oil, gas and power industries, providing construction, engineering and specialty services to industry and government entities worldwide. They place particular emphasis on projects in developing countries where they believe their experience gives them a competitive advantage. “

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