3 UK Penny Stocks With Market Caps Up To £400M

The UK stock market has recently faced challenges, with the FTSE 100 index declining amid weak trade data from China, reflecting broader global economic uncertainties. Despite these headwinds, there are still opportunities for investors interested in smaller or newer companies. Penny stocks, though an older term, continue to offer potential value when backed by strong financial health and growth prospects.

Click here to see the full list of 296 stocks from our UK Penny Stocks screener.

Here’s a peek at a few of the choices from the screener.

Simply Wall St Financial Health Rating: ★★★★☆☆

Overview: AOTI, Inc., along with its subsidiaries, focuses on producing, renting, and selling medical devices for treating severe acute and chronic wounds globally, with a market cap of £39.88 million.

Operations: The company’s revenue is primarily generated from the United States, amounting to $63.86 million.

Market Cap: £39.88M

AOTI has recently achieved profitability, reporting a net income of US$0.248 million for the first half of 2025, marking a significant turnaround from a loss the previous year. The company’s revenue increased to US$31.84 million, driven by its medical devices segment. AOTI’s topical oxygen therapy has been recognized by NICE in the UK and included in NHS Supply Chain’s Advanced Wound Care Framework, enhancing its market presence and potential revenue streams. Despite high volatility and negative operating cash flow, AOTI trades below estimated fair value with satisfactory debt levels covered by short-term assets.

AIM:AOTI Financial Position Analysis as at Nov 2025

Simply Wall St Financial Health Rating: ★★★★★★

Overview: Griffin Mining Limited is a mining and investment company focused on the exploration, development, and mining of mineral properties with a market cap of £332.14 million.

Operations: The company generates revenue primarily from its Caijiaying Zinc Gold Mine, which contributed $113.09 million.

Market Cap: £332.14M

Griffin Mining Limited has experienced a decline in net profit margins, now at 7.8% compared to 13.2% last year, and negative earnings growth of -58.6%, underperforming the industry average. Despite trading significantly below estimated fair value, its Return on Equity remains low at 3.1%. The company is debt-free with short-term assets exceeding both short and long-term liabilities, providing financial stability amidst volatility. Recent share buybacks totaling $19.24 million aim to reduce capital but follow substantial insider selling over the past quarter, raising governance concerns despite an experienced board with an average tenure of 4.2 years.

AIM:GFM Debt to Equity History and Analysis as at Nov 2025

Simply Wall St Financial Health Rating: ★★★★★★

Overview: LBG Media plc is an online media publisher operating in the United Kingdom, Ireland, Australia, the United States, and internationally with a market cap of £181.90 million.

Operations: The company generates £91.70 million in revenue from its online media publishing industry segment.

Market Cap: £181.9M

LBG Media’s recent performance highlights significant earnings growth of 281.2% over the past year, outpacing both its historical average and the broader entertainment industry. The company operates debt-free, with robust financial health as short-term assets exceed liabilities. Despite a low Return on Equity at 18.9%, it maintains high-quality earnings and improved profit margins from last year’s 5.1% to 16%. Trading below analyst price targets, LBG offers good value relative to peers with a Price-To-Earnings ratio of 12.4x against the UK market’s 16.1x, suggesting potential for future appreciation amidst stable weekly volatility at 5%.

AIM:LBG Financial Position Analysis as at Nov 2025

This article by Simply Wall St is general in nature. We provide commentary based on historical data and analyst forecasts only using an unbiased methodology and our articles are not intended to be financial advice. It does not constitute a recommendation to buy or sell any stock, and does not take account of your objectives, or your financial situation. We aim to bring you long-term focused analysis driven by fundamental data. Note that our analysis may not factor in the latest price-sensitive company announcements or qualitative material. Simply Wall St has no position in any stocks mentioned.

Companies discussed in this article include AIM:AOTI AIM:GFM and AIM:LBG.

This article was originally published by Simply Wall St.

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