With competition hotting up in a contested, post-IPG world all the remaining “big four” agency groups have had something to brag about this year as each of Dentsu, Omnicom, Publicis, and WPP has successfully claimed wins or crucial retentions to defend their turf in an increasingly high-stakes market.Beneath the high-profile pitches, however, lies a shift in client behaviour. Both WPP CEO Cindy Rose and Omnicom CEO John Wren have noted that a primary catalyst for their structural overhauls has been to drive further agency integration in order to win the biggest multi-disciplinary pitches.Speaking to Campaign earlier this year, Rose said the new Elevate28 strategy was about “stabilising” WPP’s performance through “winning new business” and “building on market momentum’.During Omnicom’s Q1 earnings call earlier this year, Wren noted that becoming a one-stop-shop for clients is an underlying trend across the industry, saying “clients are becoming more focused on selecting a single provider to take care of most of their needs”, a trend that has been reflected in reviews for both Heineken and Jaguar Land Rover this year.Adding an extra layer to holdco rivalry, Publicis Groupe chief executive Arthur Sadoun told investors in October last year that he sees a growing opportunity to win more business “without a pitch”, a pointed reference to how Publicis snatched Coca-Cola North America’s media account from WPP in a closed process last year, which has since been followed up by its win of Microsoft from Dentsu.With estimated media billings near $1bn ($924m), according to COMvergence, Microsoft’s global media remit has been the biggest account move among the holding companies so far in 2026. At an estimated $690m (COMvergence), Estée Lauder is the second largest, following a process run by Mediasense in which WPP emerged as number one.Jaguar Land Rover, Dyson, Honda Europe, Heineken, IBM and Netflix have all been in play too this year, and there’s more to come from Just Eat, Adidas and Transport for London.Here’s how the holdcos stack up so far:Dyson2025 media billings: $496m (COMvergence)Remit: Global mediaWinner: Omnicom MediaIncumbent: IPG Mediabrands/UM (Now part of Omnicom Media)In a key win for Omnicom Media post Omnicom’s merger with Interpublic, Dyson opted to keep its $502m media account within the new network after a pitch against rival holdco outfits WPP Media and Publicis Media. Omnicom Media chief executive Florian Adamski confirmed Dyson’s selection in a memo to staff, adding that the incumbent UM service team would be expanded into an “Omnicom Media solution”.Estée Lauder2025 media billings: $690m (COMvergence)Remit: Global mediaWinner: WPPIncumbent: Brainlabs (UK and Ireland), Monks (North America) and Assembly (Europe and India)WPP kicked off its year with the $690m win of Estée Lauder Companies’ global media brief in February. The review, which was handled by Mediasense, was a move for consolidation of its partners under new global chief digital and marketing officer Aude Gandon who joined in August last year.Gandon and president and chief executive Stéphane de La Faverie, who joined in January last year, were appointed to help spearhead a change in direction for the global beauty business which had been experiencing profitability struggles.At the time, de la Faverie said: “We did not capitalise on the higher growth opportunities quickly enough in channels, markets, media and prestige price tiers, nor fuel new consumer acquisition aggressively enough.”The company raised its outlook for 2026 following three quarters of growth at its Q3 results this year.Honda Europe2025 media billings: $81m (COMvergence)Remit: EMEA mediaWinner: EssenceMediacomIncumbent: UM (Now part of Omnicom Media)After nine months rolling along, Honda Europe’s EMEA media planning and buying review finally came to a close this month following a final shootout between the victor, WPP, and Omnicom.Unusually, since WPP Media switched to more collective pitching among its agencies, Honda Europe’s account was awarded to EssenceMediacom rather than a WPP Media solution. Honda is the second large automotive account win for WPP this year as the holdco also brought Jaguar Land Rover’s integrated brief into the fold this month (see below).Heineken2025 media billings: $503m (COMvergence)Remit: Global creative, production and mediaWinner: Dentsu (media), Publicis (production) and Publicis, WPP and Stagwell (creative)Incumbent: Dentsu/Dentsu X (media), Publicis/various (creative) Like Estée Lauder, Heineken’s global creative, production and media review was about reducing complexity and streamlining of its agency partnerships. There were various incumbents on the accounts, particularly in creative, but now Heineken’s model for creative, production and media globally has been refined to four holding companies.Dentsu successfully defended its 10-year relationship with the brand and secured the global media brief. For creative, the brand appointed a roster comprising Publicis, WPP and Stagwell. Within that roster, WPP will have responsibility for Birra Moretti, led by Ogilvy, and Amstel, headed up by VML, and Stagwell agency 72andSunny will work on Desperados. Publicis will continue to work on the Heineken master brand through LePub, which was not in the scope of the review. Publicis also extended its relationship with the brand to include production.IBM2025 media billings: $314m (COMvergence)Remit: Global media (Americas, EMEA, and APAC including Japan)Winner: OmnicomIncumbent: WPP MediaOmnicom pipped Publicis and Dentsu to the post in IBM’s global media review, making its second biggest win of the year so far after Dyson which it defended on behalf of the newly-bought UM a month prior.Incumbent WPP Media did not defend the account. Prior to the conclusion of the media review Campaign reported that Ogilvy, part of WPP Creative, had lost IBM's global creative after 32-years. Jaguar Land Rover2025 media billings: $487m (COMvergence)Remit: Global creative, media, production, customer experience and marketing strategyWinner: WPPIncumbent: Omnicom (media), Accenture Song (creative)Jaguar Land Rover first selected WPP as its new partner for global creative, media, production, customer experience and marketing strategy in December last year, but it took until May this year for the ink to dry on the carmaker’s new contract.In this time, the brand entered into a “period of exclusivity” with WPP to work out the finer details of their relationship. The result is an “outcome-based remuneration structure”, meaning WPP will be paid for its work dependent on its ability to meet a defined set of global business and brand metrics set by the client.WPP’s brief did not initially include media; this was added in a surprise twist in the pitch late last year.Microsoft2025 media billings: $924m (COMvergence)Remit: GlobalWinner: Publicis GroupeIncumbent: DentsuMicrosoft moved its global media account to Publicis in April. Notably, the tech giant picked Publicis without an open-market pitch , a move that chief executive Arthur Sadoun has noted as a growing opportunity for the French holding company.As part of the partnership, Publicis will use Microsoft Azure as its preferred cloud provider and make AI tool Microsoft 365 Copilot available to all staff, pitting it squarely against rival WPP, which has bet big on client Google’s AI and cloud capabilities. Netflix2025 billings: $171m (COMvergence)Region: EMEA mediaWinner: DentsuIncumbent: Dentsu/iProspectIn a second, large-scale defensive win for Dentsu, the holdco secured Netflix’s EMEA media remit after a pitch against rivals WPP and Omnicom. Both iProspect (the UK incumbent since 2023) and Carat worked on Dentsu’s pitch for the streamer, which resulted in an expanded remit covering 22 markets across mainland Europe, the Middle East and Africa – areas in which Netflix has been growing its presence.This story first appeared on Campaign UK.