Cyanotech stock gained 37.50 percent on October 6

Cyanotech stock was last at USD 0.55 in OTC trading on October 6, 2026, after gaining 37.50 percent from the previous close of USD 0.40. The company develops microalgae-based products for health and nutrition markets, including astaxanthin and spirulina, according to Cyanotech.

A sharp session move

The October 6 price increased by USD 0.15 from the prior close. The session range ran from USD 0.50 to USD 0.55, placing the last price at the top of the reported daily range.

The 37.50 percent advance was the largest numerical feature of the session for investors tracking this thinly traded OTC security. Volume reached 9,000 shares, so the price move came with a limited number of transactions rather than the turnover typical of a large listed company.

Small capitalization sets the scale

Cyanotech had a market capitalization of USD 4.1 million as of October 6, 2026. That valuation places the company firmly in the microcap segment, where individual trades can have a larger effect on the quoted price.

The 52-week range was USD 0.23 to USD 0.57. At USD 0.55, the stock stood 3.51 percent below the yearly high and 139.13 percent above the yearly low, giving the recent move a clear position within its annual trading band.

Microalgae remains the business anchor

Cyanotech says its operation in Kailua-Kona, Hawaii, uses 90 acres of cultivation ponds. Its product range includes BioAstin Hawaiian Astaxanthin and Hawaiian Spirulina, linking the company directly to dietary supplements and natural health ingredients.

The company website also reports annual electricity production of 1,147,000 kilowatt hours from a 1.3-acre solar array. That operating detail matters because the business combines agricultural production, branded supplements and contract extraction and research services.

Cyanotech stock stays below USD 0.57

Cyanotech stock was last at USD 0.55 on October 6, 2026, at 3:48 p.m. ET, while the 52-week high stood at USD 0.57. The USD 4.1 million market capitalization and 9,000-share volume underline the stock's small-capitalization profile.