As previously reported, Northcoast analyst Tom Hayes downgraded IPG Photonics (IPGP), Coherent (COHR), and nLIGHT (LASR) to Neutral from Buy as he sees considerable headwinds remaining in place, which will likely constrain unit volume growth over the next few quarters and into 2019. While the analyst continues to expect that industrial lasers, especially fiber lasers, will become an important tool in global manufacturing, the near-term challenges and lack of visibility are moving him to the sidelines as he expects the headwinds to extend into FY19 as trade and tariff issues weigh on demand. Hayes also notes that China is a significant market for laser demand, but its outsized component of total revenue adds some risk to operations. Based on the most recently published reports, trailing 12-month revenue in China represented 43% of IPG revenue, 9% of Coherent revenue, and 39% of nLIGHT's revenue, he adds.