Catch up on today's top five analyst downgrades with this list compiled by The Fly: 1. Nielsen (NLSN) downgraded to Hold from Buy at Pivotal Research with analyst Brian Wieser citing recent share strength following news of Elliott Investment Management's 8% stake in the company and maintained a $27 price target. 2. Union Pacific (UNP) downgraded to Hold from Buy at Deutsche Bank. 3. Kimberly-Clark (KMB) downgraded to Hold from Buy at Societe Generale with analyst Mitul Girotra saying pulp and oil input costs have risen sharply and cut his FY18 earnings estimate in line with management guidance. 4. Western Digital (WDC) downgraded to Market Perform from Outperform at Cowen with analyst Karl Ackerman saying his recent supply chain field work pointed to "substantial, unabated competitive pricing tactics" by the company and Toshiba (TOSBF) to gain share of enterprise and client solid state drives. 5. Tesaro (TSRO) downgraded to Hold from Buy at Argus. This list is just a portion of The Fly's full analyst coverage. To see The Fly's full Street Research coverage, click here.

BofA raised the firm's price target on Western Digital to $85 from $75 and keeps a Buy rating on the shares. The firm sees both the HDD and NAND businesses being close to the bottom of the cycle and sees a potential unlock of shareholder value as the company remains on track to split the HDD and NAND business in the second half of 2024.