CelLBxHealth PLC (AIM:CLBX, FRA:DWV) is something of a reset story and, after a turbulent few months, it looks like the pieces are starting to fall into place for the med-tech firm, with the shares up 44% this week.
A pioneer in cancer diagnostics, the business has developed a device called Parsortix that can harvest circulating tumour cells, the markers that betray the presence of disease. Its USP is that it relies on a simple blood draw rather than an invasive tumour biopsy. But there are other dimensions to this FDA-approved technology that allow doctors to more fully understand the type of cancer and the personalised treatment options available from an assay.
News flow has been progressively positive, bolstered this week by news the company has secured a collaboration with AdventHealth, one of the largest faith-based health systems in the United States. CellBx will deploy its Parsortix platform in two clinical cancer studies. Chief executive Peter Collins said the collaboration "demonstrates the growing importance of accessible, non-invasive technologies in modern oncology."
Blue-chips bask while small-caps sulk
While the FTSE 100 decisively regained ground lost in the early May sell-off, the same cannot be said of the small-cap index, where a risk-off attitude continues to persist.
Growth companies tend to underperform during periods of volatility because investors gravitate towards larger, more liquid companies perceived as safer. This leaves the market's more entrepreneurial businesses, typically more domestically exposed and carrying higher earnings volatility, more vulnerable to selling pressure. Not much fun if you're in the cheap seats.
And so it was this week, with the blue-chips up almost 3% as the AIM All-Share dropped 1.7% to 799.
CT Automotive shifts up a gear
The week's biggest riser, up 53%, was CT Automotive Group PLC (AIM:CTA), buoyed by a robust set of prelims and a strong pipeline of new business. Chief executive Simon Phillips said the ability to near-shore production from China to Mexico had become a clear competitive advantage as customers seek tariff-resilient supply routes. In short: being close to America is suddenly rather useful.
Shares in MISSION Group (LSE:TMG), the digital marketing and communications company, jumped 38% amid a flurry of director buying, including a purchase by chief executive John Carey. Director share buying matter because insiders have the closest view of a company's prospects. When multiple board members buy with their own money in quick succession, the message is fairly clear: they think the shares are cheap.
Invinity Energy Systems PLC (AIM:IES, OTCQX:IESVF, AQSE:IES) jumped 38% after it was selected by FlexBase Group to design a battery system for a Swiss technology campus set to include an AI data centre.
Mercantile Ports comes back to earth
After last week's 300% rise, it was perhaps predictable that Mercantile Ports and Logistics Ltd (LSE:MPL) would succumb to a bout of profit-taking, wiping 31% from the value of the business and making it the week's biggest loser on AIM. What goes up, and all that.
Nexteq PLC (LSE:NXQ), supplier of components to the gaming sector, slumped 21% after warning that current-year revenue will be around 15% below previous market expectations, as tariff pressure and higher component costs hit demand in its Quixant gaming technology business.
Palm oil panic: much ado about nothing?
MP Evans Group PLC (AIM:MPE), one of the larger companies on AIM, endured a rollercoaster week after an opaque Indonesian government announcement on palm oil export controls triggered a sharp sell-off across London-listed producers.
After an initial 28% plunge, the shares recovered some ground to end the week 19% lower, while smaller stablemate REA Holdings (LSE:RE.) fell 12%. Jakarta said exports of palm oil and other natural resources would be routed through a state-owned enterprise, but left critical details unresolved, including whether the scheme is mandatory, whether pricing formulas will apply and whether producer margins will be eroded.
Panmure Liberum, which rates both stocks as buys, reckons the reaction is overdone, and it is hard to disagree. Neither company exports palm oil directly; both sell to domestic Indonesian refiners, meaning any immediate impact appears limited. A subsequent government press conference suggested the new body could function merely as a recording mechanism rather than a margin-taking intermediary, with the real target being companies that use transfer pricing to minimise tax liabilities.
Following the sell-off, MP Evans trades on 8.6 times 2026 estimated earnings with an 11% free cash flow yield, while REA sits on just 4.8 times with a 26% free cash flow yield. Panmure has left forecasts unchanged for both, noting that year-to-date mill-gate prices sit comfortably above full-year assumptions, providing a built-in margin of safety.