In a significant portfolio shift, Stephen Mandel's Lone Pine Capital completely sold off its stake in optical networking firm Ciena Corp. during the second quarter of 2026. According to regulatory filings, the fund liquidated its entire holding of over 809,000 shares, which had been valued at approximately $314 million and represented about 2.5% of the portfolio at the end of March.
This disclosure, from a delayed 13F filing, reflects trading that occurred between April and June. The sale comes at a time when Ciena is experiencing high demand for its technology, driven by the expansion of AI and data center infrastructure. [4] Despite this positive trend, some analysts have recently raised concerns about supply constraints and the timing of converting its substantial backlog into revenue. [4]