On The Fly: Stocks end week lower as Yellen fails to make fireworks

Stocks ended the week lower, but not far from where they started, which is fitting considering the listless trading seen as investors awaited the Fed's Jackson Hole meeting. During the annual event, Fed Chair Janet Yellen said that the case for increasing interest rates had "strengthened," though she tempered that by saying the central bank remains "data dependent" and cannot predict when its next rate move may be made. Federal Reserve Vice Chair Stanley Fischer's comments were taken as more impactful, as he suggested that a rate hike could happen as soon as September, but even the weakness attributed to Fischer's comments was short lived and the major averages recovered by the end of Friday's trading. MACRO NEWS: In the U.S., the Chicago Fed National Activity Index improved to 0.27 in July. New home sales increased 12.4% to a 654,000 rate in July. Markit's flash manufacturing PMI fell to 52.1 in August. The Richmond Fed manufacturing index fell 21 points to -11 in August. Existing home sales dropped 3.2% in July to a rate of 5.39M. The FHFA home price index rose 0.2% to 234.8 in June. Crude oil inventories showed a 2.5M barrel build for week of August 19. Durable goods orders jumped 4.4% in July from the prior month. Initial jobless claims dipped 1,000 to 261,000 in the week that ended on August 19. Markit's flash services PMI fell back to 50.9 in August. Second quarter GDP growth was revised down to a 1.1% rate from the 1.2% pace from the advance report. The Michigan consumer sentiment reading for August came in at 89.8. Wholesale inventories were unchanged in July. Fed Chair Yellen said the case for a rate hike has "strengthened" in recent months. The economy is nearing its employment and inflation goals. She reiterated that policy is not on a pre-set course, however, and added that the Fed's ability to predict the rate path is quite limited. In Europe, the Eurozone composite PMI was 53.3 in August, little changed from the 53.2 reading in July. In Asia, Japan's flash manufacturing PMI came in at 49.6 in August. COMPANY NEWS: Mylan made headlines all week amid additional scrutiny surrounding the pricing of its EpiPen product, including criticism by presidential candidate Hillary Clinton and an information request from the Senate Special Committee on Aging. On Thursday, the company said it will be reducing the patient cost of its EpiPen Auto-Injector through the use of a "savings card," though several lawmakers, analysts and other critics said the moves the company announced were not enough to ease the burden placed on families that rely on its EpiPen in case of allergy-related emergencies... In M&A news, Medivation (MDVN) agreed to be acquired by Pfizer for $81.50 a share in cash. Rackspace Hosting (RAX) agreed to be acquired for $32 per share in cash by funds managed by affiliates of Apollo Global Management (APO). Alimentation Couche-Tard announced a definitive merger agreement with CST Brands (CST) under which Couche-Tard will acquire the company in an all-cash transaction for $48.53 per share. Pfizer (PFE) announced that it has entered into an agreement with AstraZeneca (AZN) to acquire the development and commercialization rights to its late-stage small antibiotics business in most markets globally outside the U.S... Viacom (VIAB; VIA) confirmed it has settled all legal disputes with the Redstone family and National Amusements under an agreement which will see CEO Philippe Dauman depart and COO Thomas Dooley take on the interim CEO role... Rovi (ROVI) signed a 10-year contract renewal with DISH Networks (DISH) that helped spark a rally in the company's shares... Mobileye (MBLY) and Delphi Automotive (DLPH) announced a partnership to jointly develop self-driving technology. Meanwhile, Tesla (TSLA), which has made self-driving headlines in the past, unveiled a 100 kWh battery option for the company's Model S and Model X, improving the range and driving performance of the vehicles. Two days later, the company was granted early termination by the Federal Trade Commission for its acquisition of SolarCity (SCTY)... Shares of Teva (TEVA) dropped on Wednesday after the U.S. Patent and Trademark Office's Patent Trial and Appeal Board determined that Mylan and Amneal Pharmaceuticals met their "burden of proving the unpatentability of claims 1-20 of the '250 patent by a preponderance of the evidence." The parties and Teva have been litigating over patents related to the company's Copaxone drug... On Thursday, Muddy Waters Research disclosed that it is shorting St. Jude Medical's (STJ) stock on possible cybersecurity vulnerabilities, as it believes the company's defibrillators and pacemakers can be easily compromised, causing possible fatal disruptions... Shares of Herbalife (HLF) dropped after Pershing Square's Bill Ackman, who continues to hold a "very large" net short position in the stock, was interviewed on CNBC regarding The Wall Street Journal report that Carl Icahn was recently in talks to sell his stake in the nutritional supplement maker, confirming many of the details of the Journal's report... Among companies that announced quarterly results this week, Best Buy (BBY), Nordson (NDSN), Tiffany (TIF), Guess (GES), and Autodesk (ADSK) advanced following their reports, while J M Smucker (SJM), Zoe's Kitchen (ZOES), Express (EXPR), HP Inc. (HPQ), Dollar Tree (DLTR), Dollar General (DG), Ulta Beauty (ULTA), GameStop (GME), Brocade Communications (BRCD) and Big Lots (BIG) declined. INDEXES: The Dow fell 0.83% to 18,395.40, the Nasdaq slid 0.36% to 5,218.92, and the S&P 500 declined 0.66% to 2,169.04.