GlaxoSmithKline (LON: GSK), based in Brentford, London, is one of the largest pharmaceutical companies in the world.

But its stock has been struggling as the company grapples with financial pressures like debt. Some of its largest shareholders have been paring back their holdings. Others are increasing their stake as the company issues large dividends to make up for its slumping shareprices.

GlaxoSmithKline is the result of a merger between Glaxo Wellcome and SmithKline Beecham. Current CEO Emma Walmsley is the first female CEO of the company.

Its top-selling products include Lamictal, Lovaza, Augmentin and Advair. Among its household products: Aquafresh and Sensodyne toothpastes, Nicoderm and Nicorette nicotine products and Breathe Right nasal strips, among many others. GlaxoSmithKline developed several products noted by the World Health Organization as essential products: zidovudine AIDS treatment, purinethol used for cancer treatment and antibiotic amoxicillin. (See also: GlaxoSmithKline Launches Anemia Drug.)

Glaxo continues to make strides in many fields. Recently, and in partnership with Innoviva Inc. (INVA), GlaxoSmithKline announced positive results from a U.S. phase-three study of a triple-therapy inhaler to treat chronic pulmonary disease. The inhaler, called Trelegy Ellipta, is approved by the U.S. Food and Drug Administration. Its product pipeline also includes HIV drug regimens filed for approval in the U.S. and E.U.

However Glaxo is challenged with sliding profits and significant debt in part from restructuring charges. Its shares are down about 10 percent on the London Stock Exchange as of Sept. 29. To try to make up for that lost value, the company now offers an annual dividend with about a 4.84 percent yield. (See also: GlaxoSmithKline up Slightly After Results.)

GlaxoSmithKline’s largest shareholders include mutual funds, which hold $24.5 billion worth of shares, and financial institutions, which hold $25.9 billion worth, according to Morningstar. Insiders hold about $2.5 billion in the company’s stock.

Here are the top shareholders, according to Morningstar:

Top Five Mutual Fund Holders:

VA CollegeAmerica Inc. Fund of America holds 60.5 million shares, or a 1.2 percent stake, as of June 30, 2017. It recently shed 2.2 million shares. That accounts for 1.23 percent of the fund’s total net assets.

Vanguard Total Intl. Stock Index holds 61.5 million shares, or 1.25 percent stake, as of Aug. 31, 2017. It recently added 671,500 shares.

VA CollegeAmerica Cap. Inc Bldr holds 28.6 million shares, or a 0.58 percent stake, as of June 30, 2017. It recently dropped about 7 million shares. That accounts for about 0.6 percent of its net assets.

Vanguard Developed Markets Idx Admiral holds 24.5 million shares, or a 0.5 percent stake, as of Aug. 31, 2017. That accounts for about 0.5 percent of its total assets.

Federated Strategic Value Dividend A holds 18.2 million shares, or a 0.37 percent stake, as of June 30, 2017. That accounts for about 2.8 percent of its total assets.   

Top Five Institutional Holders:

Vanguard Group holds 103.9 million shares, or a 2.1 percent stake as of Aug. 31 2017. That accounts for 0.5% of its total assets. It recently shed 6.3 million shares.

Capital Research and Management Company holds 93.7 million shares, or a 1.9 percent stake in Glaxo as of June 30, 2017. It recently shed 12.6 million shares.

BlackRock Fund Advisors holds 73.4 million shares, or a 1.5 percent stake as of Sept. 28, 2017. It recently added 753.4 million shares.

Fidelity Management and Research Co. holds 58.5 million shares, or a 1.2 percent stake in Glaxo as of July 31, 2017.

BlackRock Investment Management holds 38.6 million shares, or a 0.8 percent stake as of August 31, 2017. That represents about 2.1 percent of its total assets.

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