Wanjigi succession battle: Widow, son fight over billionaire's empire
Crime and Justice
By
Kamau Muthoni
| Oct 18, 2026
When Maina Wanjigi lived, he built a multi-billion-shilling empire and quietly slipped away to eternal sleep.
Other than in one instance in 2018, when he came out to condemn the then government after the raid on his son’s home, the reclusive politician kept off the media's glare.
However, the quiet he lived and perhaps hoped for after his departure by writing a will did not come to pass.
The former minister's family has ended up on the list of heirs in the corridors of justice, battling one another over the wealth left by patriarchs and matriarchs.
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From the exchanges seen by Sunday Standard, the succession differences have spilt over to court and the police.
On one hand is the deceased’s son, Sonny Mbui Wanjigi, also roping in his son Michael Maina. On the other are Wanjigi’s widow, Mary Wambui and another son, Jimi Richard Wanjigi.
Maina left his widow and two sons as executors of the will and trustees. He also directed that lawyer Elms Guy Spenser should replace any of the three in case they declined to take up the role.
The quiet that the family enjoyed quickly turned into loud differences immediately after Justice Hilary Chemitei allowed the family to move ahead with the administration and distribution of the wealth.
Mbui was first, questioning the details of the trust and claiming that some companies had been left out, and transfers were allegedly done without his participation and consent.
In the meantime, his mother and brother want him out, urging the court to direct that he be removed as an executor.
Mbui argued that although his late father had established an eight-year trust, which was meant to benefit his future generation, it allegedly received modest assets while the lion’s share of the estate allegedly went outside it.
“The documentary record reveals a consistent and coherent intention that a substantial portion of the deceased’s estate would be preserved within the trust for the future generations. The interpretation advanced by my co-executors and co-trustees produces an outcome that sits uneasily with that intention and with the written instructions the deceased personally prepared, reviewed and preserved,” he argued.
He asserted that his main issue was whether the will was a reflection of his late father’s wishes.
Jimi gave his mother the authority to appear, plead and act on his behalf in the case.
Mbui alleged inconsistencies in the properties listed as the wealth left behind by the former minister.
He claimed that they had attended meetings at the family’s offices and their mother’s residence over the same. According to him, Spenser allegedly indicated that changes be made to the records and directorships of companies through which the estate assets were held, to facilitate dealing in those companies outside the succession process.
He alleged that after a search, he allegedly discovered that there were changes that had been made.
He cited alleged changes in Chania Merchants Limited, East African Office Equipment (1976) Limited, Kitamaiyu Limited, Kianjoya, Nine Sisters Limited, Nine Sisters Management Karen Limited, and Chepe Chepe Limited.
Mbui maintained that he did not give a green light for the same to happen.
He also claimed that some four properties had allegedly been disposed of.
On the other hand, his mother argued that the issues he raised were meant to allegedly delay the succession process.
In her response, Wambui argued that her son’s grievances were based on selective and erroneous interpretation of his late father’s wishes. She said that her husband was fully aware of what the will dated August 31, 2000 provided for his estate and what was to go to Kwacha.
Wambui stated that the four properties her son had cited were disposed of during the deceased’s lifetime.
“Contrary to the applicant’s assertions, we have at all material times acted diligently, transparently and in good faith in the administration of the estate... I am an elderly lady, and I have no intent of delaying in the administration of the estate, and if any delays are being occasioned by the applicant, on the advice of our advocates on record, I shall appropriately move to have the Deputy Registrar execute the transmission documents in place of the applicant, she said.
She insisted that he initially was participating in the administration process, including attending meetings.
Spenser also replied to the Mbui’s claims in court. He admitted drafting the will in 2000. According to him, at the time of inception of the trust, the fund was holding Sh100 only. However, Maina had the discretion to add more assets and or investments to the trust during his lifetime.
He stated that the senior Wanjigi, at 69 years when his will was written, directed that any of the properties that were not part of the will were to devolve to Kwacha.
“ I can confirm that the respondents are correctly following the deceased’s express intentions and instructions set out in the will dated August 31, 2000 and therefore there is no inconsistency in the administration of the estate or the trust or inconsistency with the certificate of confirmation of grant or the availability of the trust,” said Spenser.
Mbui’s mother also struck back. Her lawyer Harshil Shah, filed an application before the court, seeking the removal of Mbui as an executor. He cited an alleged breach of trust, claimed the transfer of assets forming Maina’s estate and alleged failure to meet so that they could plan the way forward to administer the estate.
Shah also claimed that Mbui had allegedly refused to sign documents to facilitate distribution of the wealth and obstructed the process by allegedly refusing to participate in or agree to necessary steps.
“ The applicant’s conduct is inconsistent with his duties as an executor and poses an imminent risk of further dissipation and loss of the estate’s assets. It is in the best interest of the estate and all the beneficiaries that the applicant herein be removed as an executor and restrained from any further acts of maladministration and obstruction, which pose an imminent risk of further dissipation of the estate assets pending the hearing and determination of this application,” argued Shah.
He further urged the court to issue Wambui and Jimi a new grant.
In her supporting affidavit, Wambui claimed that her son had allegedly transferred a vehicle without consent to her grandson Michael. The vehicle, according to her, is owned by Chania Merchants Limited.
Mbui denied his mother’s claims, saying that it was allegedly done with her approval.
He claimed that Wambui allegedly sought advice on the management of annual inspection process of two vehicles at the heart of their differences. He said that she alongside her grandson, allegedly jointly undertook the inspection process, after which they also allegedly struck an agreement to relieve her from the tedious job.
“My mother and my son jointly and effectively transferred the vehicles to the latter to simplify the administrative requirements associated with inspection and compliance; and
In a further reply, she argued that she never participated in the same. The transfers were completed through the NTSA system using security codes lawfully received on my mother's mobile phone,” he replied.
He insisted that there is no evidence produced in court to link him to any fraud. He urged the court to dismiss the application for his removal as an executor, adding that the grant should remain intact.
Mbui said he was willing to participate in the process but only if his father’s wishes were honoured to the letter.
“ My position has consistently been that I am willing to co-operate in the administration of the estate but cannot in good conscience execute documents giving effect to a distribution that I genuinely believe is contrary to the deceased’s wishes and the law,” he replied.
Michael also replied to his grandmother. He echoed his father’s response. He first stated that his father had nothing with the transfer of the vehicles. At the same time, he said he did not instruct him to do so.
Instead, he claimed he had previously assisted his grandmother in the inspection of the two.
According to him, the transfer was a mutual agreement between a grandmother and a grandson for change to facilitate further management and not taking away anything from his grandfather’s estate.
“ At the time, neither my grandmother nor I regarded the transfer as a disposal of the two motor vehicles for value or as a transaction intended to deprive any person of an interest in them. The transfer was undertaken solely to simplify their administration,” claimed Michael.
His grandmother, on the other hand, asserted she had nothing to do with the transfer.
“ Confronted with this fact, I am aware that Sani, in his supplementary affidavit, denied any involvement in the alleged transfers and instead stated that the same was done with my approval together with his son Michael Maina Mbui Wanjigi. This is entirely untrue as I did not participate in the fraudulent transfers, as the same would be inconsistent with my husband’s will... The signatures on the said statutory declarations are not mine and do not resemble my signature at all,” she replied.
Maina studied at Kagumo in Nyeri and Alliance Schools before going to Makerere University in Uganda, and thereafter heading to the US where he earned his Master's degree in economics before Kenya gained independence.
Upon returning to the country, Wanjigi worked as an assistant agricultural extension officer in Nyeri District, in the colonial administration, and that is probably how he developed his profile that made him director of settlements.
The resettlement exercise, however, created a lot of discontent and controversy, especially from some Mau Mau freedom fighters who claimed they were never given land despite the role they played in the struggle for independence.
But satisfied that he had done a good job, President Jomo Kenyatta appointed him the Chief Executive of the Industrial and Commercial Development Corporation (ICDC) in 1968, ostensibly to now empower the commercial capacity of local communities.
He was expected to ensure that as many local people as possible engaged in trade, an area that at the time was largely controlled by Asian dukawallas (shop owners), while the manufacturing sector was still under the ownership of white businessmen.
Maina then established the Kenya National Trading Corporation (KNTC) and Kenya Industrial Estates (KIE) that successfully drove and supported local businesses. The two agencies collapsed in the early 1980s because of mismanagement and corruption.
He later joined politics in 1969, when he vied for the Kamukunji parliamentary seat and won after the assassination of the then area MP, the late Tom Mboya, on the streets of Nairobi.
President Kenyatta appointed him an Assistant Minister for Agriculture and that made him one of the most influential politicians who never served in a full ministerial capacity before the first president died in 1978.
He was also appointed to plum ministerial dockets, which included ministries of Public Works and Housing, Cooperatives Development, Tourism and Wildlife and later Agriculture.
He later fell out with President Daniel Arap Moi when another purge was executed by the government after opposition leaders led by Kenneth Matiba, Martin Shikuku, Masinde Muliro and Oginga Odinga began agitating for multi-party democracy.
After politics, the former MP took a low profile, focusing on developing and managing his large business empire that included the Kwacha Group of Companies.