An employee of Boston-based biotech company PixarBio Corp. pleaded guilty last week to securities fraud charges in connection with a scheme to defraud investors and manipulate the company’s shares.

M. Jay Herod, 52, of Cambridge, pleaded guilty to one count of securities fraud and one count of obstruction of an agency proceeding. Herod was initially charged by criminal complaint and arrested with co-defendant Frank Reynolds, the former CEO of PixarBio, in April 2018. Reynolds has pleaded not guilty.

Herod admitted that, beginning in or about December 2016, he engaged in manipulative trades in PixarBio stock that were intended to simulate market demand for the stock and thereby artificially inflate its price and trading volume.

The trades included overlapping orders to buy and sell PixarBio shares at the same price per share (a manipulative technique known as “matched trading”), as well as small purchases submitted shortly before the market closed that were intended to boost the closing price (a technique known as “marking the close”). Herod admitted to sharing the proceeds of his trading with Reynolds and PixarBio itself.

Herod also admitted that, between January 2017 and September 2017, he made materially false statements to the Securities and Exchange Commission and provided a back-dated document to the SEC, with the intent to obstruct the SEC’s investigation of trading in PixarBio shares.