In May 2025 a fierce dispute erupted between small Johannesburg-listed miner Mantengu Mining (MTU), rival Liberty Coal, and the Johannesburg Stock Exchange (JSE). Mantengu accused the JSE and certain market players of deliberate share-price manipulation that, it says, depressed MTU’s value and sabotaged a strategic deal. The JSE and Liberty Coal have strongly rejected the claims and pushed back with legal warnings and actions. The row has drawn scrutiny from regulators, sparked heated media coverage, and raised uncomfortable questions about market integrity and how small issuers are protected.
What Mantengu alleges
Mantengu’s core claim is that a coordinated campaign of short-selling and other market tactics drove its share price down, harming shareholders and undermining a planned acquisition (the Blue Ridge deal). After about 18 months of internal investigations, Mantengu filed a criminal complaint with the Hawks — South Africa’s Directorate for Priority Crime Investigation — naming individuals and alleging institutional failures at the JSE to act on prior warnings. The company produced a lengthy dossier it says shows suspicious trading patterns and “front companies” linked to parties that would benefit from MTU’s depressed valuation.
The JSE and Liberty Coal responses
The JSE responded decisively: it described Mantengu’s allegations as “vexatious and without merit,” rejected any suggestion that its staff participated in manipulation, and issued a cease-and-desist demand to Mantengu over public statements. JSE officials said they would not allow exchange staff to be dragged into unfounded litigation. Liberty Coal — which Mantengu named among the alleged conspirators — also denied wrongdoing and moved to protect its reputation, filing for R250 million in defamation damages in the Gauteng High Court. Both parties have signalled readiness to litigate rather than negotiate in public.
What regulators found (so far)
Following Mantengu’s complaint, South African regulators reviewed trading data. The Financial Sector Conduct Authority (FSCA) conducted an inquiry into the specific trades Mantengu flagged and publicly reported it did not find evidence of naked shorting at the company in its review. That finding has been used by critics of Mantengu’s public accusations to argue the company overreached. However, Mantengu has continued to insist there are unanswered questions about broader market behaviour and the adequacy of exchange oversight.
Why the dispute matters beyond the companies involved
Market integrity and confidence. Allegations that a bourse or market participants can be co-opted to manipulate prices strike at investor trust. Even unproven claims can spook investors and reduce liquidity for small-cap issuers.
Small-company vulnerability. Smaller listed companies often lack the resources to counter sophisticated short-selling strategies, or to mount long investigations — and so public accusations become one tool to force action or attention. That dynamic can create a messy public spectacle.
Regulatory adequacy. The FSCA’s findings will matter, but questions remain about the depth and scope of reviews, the transparency of outcomes, and whether exchanges have appropriate early-warning systems for suspicious trading.
Legal and reputational fallout. Defamation suits and cease-and-desist letters suggest the row will play out in courtrooms and media as much as in market data, with reputational harm likely irrespective of legal outcomes.
Practical timeline of events (short)
Early 2024–2025: Mantengu monitors and investigates unusual trading it believes targeted MTU.
May 2025: Mantengu publicly files a criminal complaint with the Hawks alleging share-price manipulation and names Liberty Coal and certain individuals. The JSE issues a cease-and-desist demand to Mantengu and publicly rejects the allegations. Liberty Coal launches a R250m defamation claim. The FSCA reviews trades and reports no evidence of naked shorting in its specific review.
Reading the competing narratives fairly
Mantengu’s position: It says the available evidence — internal trade analyses, common directors and advisors across alleged front companies, and the timing around a takeover attempt — point to targeted manipulation. Mantengu frames its disclosures as a defence of minority shareholders and a bid to force proper investigation.
JSE/Liberty’s position: They maintain the claims are unfounded, have denied involvement, and stress that the regulator (FSCA) and the exchange’s own surveillance detected no systemic malpractice in the trades examined. From their perspective, Mantengu’s public accusations caused reputational damage and risked misleading investors.
What investors and market participants should watch next
Legal outcomes: Watch the progress of Liberty Coal’s defamation suit and any court rulings on Mantengu’s criminal complaint — courts may publish key findings or rulings that clarify disputed facts.
Regulatory statements: Any expanded FSCA or exchange investigation outcomes, or further disciplinary actions, will be pivotal. Regulators may widen their probe or publish fuller reports.
Trading patterns: Independent market analysts and data vendors may flag recurring patterns; sustained irregular trading would strengthen Mantengu’s case, while absence of such evidence will favour the exchange and Liberty.
Media and reputational developments: Public statements, rebuttals, and corporate filings (SENS announcements for JSE-listed entities) will shape investor sentiment short-term.
FAQs
Did the FSCA find evidence of naked shorting at Mantengu?
The FSCA’s review of the trades identified by Mantengu reported it found no evidence of naked shorting in that specific review. That finding has been cited by the JSE and others to rebut Mantengu’s broad allegations. However, Mantengu disputes that the regulator’s review fully addressed all its concerns.
Has the JSE been accused of wrongdoing before?
This is not the first time exchanges face public criticism, but a direct criminal complaint alleging staff collusion is unusual and serious. The JSE’s public denial and legal posture show it is treating the allegations as damaging and unfounded.
Could this affect other listed small-cap companies?
Yes. If investors perceive higher risk that small caps are vulnerable to manipulation or to reputational volatility, some may avoid investing — which reduces liquidity and can raise capital costs. Conversely, regulatory clarification or court rulings could restore confidence.
What remedies are available to Mantengu if manipulation is proven?
If courts or regulators find wrongdoing, remedies could include criminal prosecutions, civil damages, trading sanctions, and possible compensation for harmed shareholders. If the claims are not substantiated, Mantengu risks counter-litigation for defamation.
Should retail investors act now on this story?
Retail investors should avoid knee-jerk trades based solely on headlines. Check verified company filings (SENS notices), regulator releases, and reputable financial press for developments. Consider the company’s fundamentals and risk appetite before making decisions.
Conclusion — a dispute that tests systems, not just companies
The Mantengu–Liberty–JSE conflict is more than a feud between rivals; it is a live test of South Africa’s market oversight, the protections available to small issuers, and how allegations spread in the digital media age. At present the balance of public evidence and regulatory statements has not produced a definitive finding of manipulation — the FSCA reported no evidence of naked shorting in the trades Mantengu highlighted, and the JSE has firmly denied wrongdoing. Yet the appearance of a contested criminal complaint, coupled with defamation claims and heated media coverage, means reputational damage is already significant.
For investors and market-watchers the sensible posture is cautious: follow court filings, regulator statements, and verified market data rather than social media claims. For regulators and the exchange, this episode is an opportunity to increase transparency about surveillance processes and dispute-resolution mechanisms so that small companies and ordinary investors can have greater confidence that suspicious trades are investigated quickly, and that public allegations are matched by formal investigative findings.
