Sean O’Shea is Managing Principal of Sienna Capital Partners with expertise in strategic advisory, capital markets, and direct and indirect real estate investing.

Prior to founding Sienna in 2011, Sean was a Fund Manager within the Global Real Estate Multi‐Manager Group of Aviva Investors with then over $8.7 billion in AUM. He joined Aviva Investors in 2008 as part of its U.S. acquisition of Madison Harbor Capital. Sean was a senior member of Aviva’s Americas investment team based in New York. He was later seconded to London where he served on Aviva’s European investment team.

During his tenure at Aviva and Madison Harbor, Sean managed four co-mingled real estate funds of funds that invested in value-add and opportunistic strategies in developed and emerging markets.  His responsibilities included portfolio management, investment selection, and asset management. He reviewed over 1,700 fund strategies and interviewed over 300 management teams. His investment activity focused on co-mingled funds, secondary interests, and distressed recapitalizations of funds and portfolios.  Prior to joining Madison Harbor in 2006, Sean was a member of the acquisition team of Gould Investors L.P. where he invested in retail, office and multifamily properties.

Sean received his BA from Rutgers University, MBA from Georgia State University and MS in Real Estate from New York University.  He has been a member of the Urban Land Institute, the International Council of Shopping Centers, the Pension Real Estate Association and the Family Office Association.  Sean is an active alumnus of New York University, where he has been a guest lecturer, an Alumni Chapter Board member of the NYU SPS Schack Institute of Real Estate and currently serves as an Alumni Board member of NYU’s School of Professional Studies.

Anne Oh is a Principal at Sienna Capital Partners with expertise in fund placement and investor relations.

Previously, Anne served as Managing Partner at Wren Capital where she joined at its inception in 2009 to build the firm’s alternative investment placement platform. Wren concentrated on a select number of fund managers providing capital raising and advisory services across a suite of alternative investment mandates including private equity, real estate, energy, private debt, credit, venture, hedge funds, and secondaries. Anne engaged on investment offerings that successfully raised in excess of $2bn of equity capital on behalf of domestic and international general partners.  Anne maintains a broad network of institutional investor relationships including public pensions, private and corporate pensions, insurance companies, endowments, foundations, consultants, and wealth managers.

Prior to Wren, Anne served as Vice President at Merchant Forecast, an independent research firm focusing on the U.S. specialty retail sector where she developed a loyal client base of institutional investors including long-only managers, hedge funds and other financial sponsors. Anne gained her capital markets experience at Merrill Lynch, which extended across the public market continuum including Emerging Europe equities, fixed income, credit derivatives, asset swaps and structured products.  During her seven years at Merrill, Anne held various positions including institutional sales and product management, most notably serving as the inaugural National Fixed Income Product Manager to lead the sales effort of a 110-person sales team in the firm’s Middle Markets division.

Anne holds a BS degree from University of Maryland and MBA from University of Chicago Booth School of Business.  Anne holds FINRA Series 3, 7, 24 and 63 securities licenses.

Wiebke Wanner-Borchardt is a Principal at Sienna Capital Partners with expertise in fund placement, investor relations, and direct and indirect real estate investing.

Previously, Wiebke was Managing Director at CrossCon Real Assets Capital which she joined in 2015 to support the firm’s real estate investment placement business. Wiebke engaged on investment offerings on behalf of domestic and international general partners targeting investors in the US, Europe and Asia.

Prior to CrossCon, Wiebke served as Director of Business Development as a member of TIAA’s Institutional Sales Team. During her eleven years at TIAA, she held a number of positions including Director of Real Estate and Special Assistant to the CEO where she developed expertise in direct and indirect real estate investing, portfolio management and corporate strategy. Most notably, Wiebke was tasked to expand the firm’s sales efforts for real assets and fixed income products into the German speaking markets and was a founding member of the firm’s Globalization Team. Wiebke developed an expansive network of global institutional investor relationships including public pensions, private and corporate pensions, insurance companies, endowments, foundations, consultants, and wealth managers.

Wiebke holds an MS degree from University of Regensburg in Germany, an MBA from University of Connecticut School of Business and a Graduate Certificate in Real Estate from New York University. She is a member of the Investment Advisory Board for the University of Connecticut’s Student Management Fund, a mentor for graduate students of the full-time MBA program and an industry representative to the School of Business’ project related task force. She is fluent in English, German and French and holds FINRA Series 7 and 63 securities licenses.


Steven Rosa is a Vice President at Sienna Capital Partners with expertise in strategic advisory, capital markets, and direct real estate investing.

Previously, Steven served in the Real Estate and Lodging Investment Banking group at J.P. Morgan, where he provided comprehensive strategic advisory and capital raising services to private and public clients, including REITs, financial sponsors, and real estate operators. He advised sellers and acquirers on merger, acquisition, and leveraged buyout transactions. While at J.P. Morgan, Steven completed over $7.3 billion of capital markets transactions including secondary equity, high yield and investment grade bond, and syndicated loan offerings.

Steven also previously served on the acquisitions team of a private real estate investor and operator focused on value-add multifamily and retail investments in the New York metropolitan area. His responsibilities included underwriting and financial analysis, pipeline development, and investment recommendations for the firm’s investment committee.

Steven holds a BA in Financial Economics from Columbia University, and an MS in Real Estate with a concentration in Finance & Investment from New York University. He is a veteran of the U.S. armed forces and served overseas during Operation Iraqi Freedom. His real estate industry trade association affiliations include ULI, NAIOP, ICSC, CREFC, FIABCI, and the Appraisal Institute. Steven holds FINRA Series 63 and 79 securities licenses.