Valter Olkkonen

Senior Associate, Member of the Finnish Bar

I assist our clients in various financing transactions.

Before joining Castrén & Snellman, I worked as a trainee at a major law firm in the United Kingdom and at a Big Four accounting firm in Finland.

In addition to my Master of Laws degree from the University of Helsinki, I have studied law at the University of Edinburgh.

Latest references

We advised Aktia Bank Plc on the issuance of an EUR 80 million Additional Tier 1 (AT1) bond. The bond pays a fixed interest rate of 6.75 per cent semi-annually. The bond is perpetual, and Aktia has the right to redeem or repurchase it in accordance with the terms of the bond, subject to certain conditions. The bond was issued on 1 April 2026. In addition, we assisted Aktia in listing the bond on the Nasdaq Helsinki Ltd stock exchange. For the listing, we prepared Finland’s first EU Follow-on prospectus for a bond. The EU Follow-on prospectus was introduced on 5 March 2026 with an update to the Prospectus Regulation (EU) No. 2017/1129. The EU Follow-on prospectus is a new type of prospectus that can be used, among others, by issuers whose securities have been admitted to trading on a regulated market continuously for at least the 18 months preceding the offer to the public or the admission to trading on a regulated market of the new securities. A follow-on prospectus is simpler than a so-called traditional prospectus, and it is intended to avoid repeating information that the issuer has already disclosed. Nordea Bank Abp acts as the sole structuring advisor for the issue of the Notes. Nordea Bank Abp, Danske Bank A/S and ABN Amro Bank N.V. act as the lead managers for the issue of the Notes. 
Case published 7.4.2026
We advised CapMan Infra’s portfolio company Koiviston Auto Group, Finland’s largest bus operator, in a finance arrangement in which it completed an approximately EUR 300 million refinancing. The transaction consists of the refinancing of the Group’s existing senior debt and secures long-term growth financing to support the Group’s continued investments in its rapidly expanding electric bus fleet. The financing package has been provided by a group of lenders consisting of Nord/LB, ABN AMRO, Edmond de Rothschild, LBP AM and Siemens. The transaction strengthens Koiviston Auto’s funding base and provides significant flexibility to execute the company’s growth strategy focused on sustainable public transportation. CapMan Nordic Infrastructure I acquired Koiviston Auto in December 2021 to support its expansion and operational development. The Group now serves communities nationwide and is at the forefront of the transition to zero-emission public transport in Finland. It operates approximately 300 electric buses, with more than 50 additional electric buses expected to be deployed into traffic during 2026, further accelerating the electrification of its fleet. “The successful completion of this refinancing marks an important milestone for Koiviston Auto Group,” says Henrik Mikkola, CEO of Koiviston Auto Group. “The strong support from a diversified group of high-quality lenders underlines the robustness of our business and our long-term strategy. This financing allows us to continue investing in electric mobility and to provide reliable, sustainable and high-quality public transport services across Finland.” “Koiviston Auto Group plays a key role in the green transition of public transportation in Finland,” comments Ville Poukka, Managing Partner at CapMan Infra. “This refinancing significantly strengthens the company’s financial platform and enables continued investments into electric buses at scale. We are pleased to see strong lender confidence in the company’s strategy, operational performance and long-term growth prospects.”
Case published 25.3.2026
We advised Fingrid Oyj on the Finnish law aspects in the update of a EUR 3 billion Euro Medium Term Note programme (EMTN). Notes issued under the programme may be listed on the Irish Stock Exchange. Fingrid operates Finland’s main electricity transmission grid and all significant cross-border transmission connections. The main grid is the backbone of the electricity transmission network, to which major power plants, industrial plants and regional electricity distribution networks are connected.
Case published 17.3.2026
We advised a leading global investment firm Brookfield, alongside a global sovereign wealth investor, on the Finnish law aspects of a EUR 1 billion holdco financing for DayOne Data Centers, a Singapore-headquartered developer and operator of hyperscale data centres. Structured as a seven-year secured holdco financing facility of €500 million, expandable to €1 billion – and secured by DayOne’s Finland platform – the financing will support the rollout of hyperscale developments in Lahti and Kouvola, providing nearly 300MW of planned capacity across Finland. The proceeds will also support DayOne’s global expansion across the EU and APAC, with flexibility to allocate to other key growth markets as required.
Case published 29.1.2026
We advised OP Corporate Bank and Skandinaviska Enskilda Banken (SEB) in the EUR 200 million financing of Sello Shopping Centre, one of the Nordic countries’ largest and most diverse shopping centres. The shopping centre is owned by Finnish pension insurance companies Keva, Elo and Ilmarinen. Sello is a pioneer in sustainable development, featuring an intelligent energy system and 2,300 solar panels. The shopping centre holds the highest LEED Platinum environmental certification, becoming the first shopping centre in Europe to achieve this distinction. Sello has demonstrated outstanding operational performance throughout 2025, achieving record visitor numbers and sales figures. 
Case published 29.1.2026
We advised S-Bank Plc in its issuance of a EUR 150 million Senior Non-Preferred Notes and on the tender offer of its EUR 150 million Senior Preferred MREL Eligible Notes maturing in 2026. The tender offer required prior approval from the Finnish Financial Stability Authority based on the Commission’s regulatory technical standards (EU) 2023/827. The Stability Authority granted S-Bank a permission for repurchases of the notes. Based on the permission, S-Bank replaced the notes with own funds or eligible liabilities instruments of equal or higher quality at terms that are sustainable for the income capacity of S-Bank. According to the final tender offer results published on 10 December 2025, S-Bank repurchased a total of EUR 97.9 million of the notes. The new notes will pay a floating interest rate, which is determined based on 3-month Euribor added with a margin of 1.35 per cent. The notes were issued on 11 December 2025 and listed on Nasdaq Helsinki Ltd. The maturity date of the notes is 11 December 2029. The purpose of the issue was to meet the minimum requirement for own funds and eligible liabilities (MREL) and to finance the bank’s activities.
Case published 18.12.2025
We advised Ålandsbanken Abp in the consent solicitation process regarding its SEK 150,000,000 Tier 2 notes due December 2041 and SEK 200,000,000 Tier 2 notes due March 2043. The terms and conditions of the aforementioned instruments were amended by removing the write-down mechanisms in the consent solicitation process. In addition, we advised Ålandsbanken Abp on the issue of SEK 350 million Additional Tier 1 notes. The notes bear floating interest at the rate of STIBOR three months plus a margin of 3.35 per cent per annum. The AT1 notes were issued on 20 November 2025, and admitted to trading on the official list of Nasdaq Helsinki Ltd. The instrument has no maturity date and qualifies as Additional Tier 1 capital in accordance with the EU Capital Requirements Regulation. The issue strengthens Ålandsbanken’s capital structure by taking advantage of favourable market conditions.
Case published 10.12.2025
We advised CapMan Real Estate in the acquisition and financing of a high-quality residential asset located in Katajanokka, Helsinki.  The asset was acquired from the Finnish Seamen’s Service Bureau (MEPA).  The property consisting of 38 modern rental apartments with a parking garage was completed in 2017. The building features high-quality construction, modern floorplans, and well-designed communal areas including a gym and rooftop sauna premises, and blends with the area’s historic maritime character. The residential asset is located in the prestigious Katajanokka seaside district of central Helsinki, known for its architectural heritage and proximity to the city centre. The property has a high ESG profile which will be further improved by CapMan Real Estate.
Case published 6.11.2025