The filing for April 29 was disclosed on May 3 and it is not yet clear if JP Morgan has made further transactions since then.
AEM, which closed at $7.35 on April 30, is on a tear following a wave of upgrades by analysts, cheered by how it is both poised to win new orders from its existing key customer and is also well positioned to win significant new orders from other new customers.
JP Morgan first emerged as a substantial shareholder of AEM Holdings on March 16, when filings indicated that it paid $3.35 on average for 555,000 shares, bringing its interest to 5.19%.
Since then, it made a series of trades, at times trimming, but on aggregate increased its position as AEM ran up strongly.
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On March 17, JP Morgan sold 910,200 shares at $3.53 each but also bought 22,300 shares via a prime brokerage arrangement.
On March 26, it paid an average of $4.49 each for just over 1.94 million shares but also sold 147,800 shares.
On April 10, it paid an average of $4.69 for another 1,070,900 shares. On April 20, it paid an average of $4.86 for another 115,600 shares.
