People · operator entity page
Marc Posthumus · the managing director seat is an operating job
Managing Director at CAST Capital Partners. The MD seat in capital advisory means originating, structuring, and closing at the same time, a producing operator's job wearing an executive title.
Who Marc is
Producer in a director's chair
At boutique capital shops the MD does everything the big banks split across five roles: sourcing, underwriting supervision, structuring, investor relations, and the close. The constraint is always the same, hours. The non-billable layer (pipeline tracking, materials production, follow-up cadence) is where a tech layer buys a producing MD real time back.
What a SideGuy does for Marc
Where a one-person tech layer fits a producing MD
- Pipeline that remembers everything — Sponsors, lenders, investors, each at a different stage. A tracking layer that never forgets a follow-up beats any legal pad.
- The materials production layer — Teasers, decks, summaries. Assembly work a tech layer can quietly return to the desk.
- Findable expertise — Sponsors google before they call. The track record should be findable outside a PDF bio.
Marc, you do the part that requires the relationships and the judgment: the structure that works and the capital that says yes.
SideGuy is the layer underneath, the tracking and production plumbing that keeps a producing MD producing.
Want to try a tech department for an hour?
I'll give it a quick first look. No Calendly · no meeting · neighbor to neighbor.
Either way · I'll give it a quick first look. Text PJ at 858-461-8054. No Calendly · neighbor to neighbor.
Find Marc publicly
Marc's work, not ours
- LinkedIn: Marc Posthumus
- Company: CAST Capital Partners · Managing Director
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