Is Illumina, Inc. overvalued or undervalued?

As of 31 October 2025, the valuation grade for Illumina, Inc. has moved from fair to expensive, indicating that the company is overvalued. Key valuation ratios include a P/E ratio of 26, a Price to Book Value of 6.89, and an EV to EBITDA of 9.89, which are significantly higher than its peer Biogen, Inc., which has a P/E of 13.57 and an EV to EBITDA of 8.89. This suggests that Illumina is trading at a premium compared to its industry peers.
In terms of performance, Illumina's stock has underperformed against the S&P 500 over multiple periods, with a year-to-date return of -7.55% compared to the S&P 500's 16.30%. This trend continues over longer periods, with a 3-year return of -44.45% versus 76.66% for the S&P 500, reinforcing the notion that Illumina is currently overvalued.