On Monday, shares of optical communications firm Applied Optoelectronics (AAOI.US) opened sharply lower, dropping more than 16% at the time of writing.

The decline comes as the company revealed plans to raise $600 million through a stock offering, intensifying investor concerns over further equity dilution. This marks yet another fundraising move for Applied Optoelectronics, which has repeatedly tapped similar financing mechanisms this year.

Earlier, in April, the company completed a $500 million at-the-market (ATM) offering, followed by another $600 million raise in May. With shareholders already absorbing substantial dilution this year, the latest filing signals the onset of yet another large-scale share issuance, adding further pressure on the stock.