This is the creative team's first permanent agency position after short-term experience at TBWA/GGT and 23 Red.
Both brothers graduated from Buckinghamshire Chilterns University with a BA in advertising and graphic design.
Darrio, 27, studied at Central St Martins and Claus, 24, went to Kingston University and both secured a National Diploma in foundation studies.
The brothers have won awards for their work including a Student D&AD for direct mail and creative writing.
Bob Nash, creative director at Clark McKay and Walpole, said: "In my 20 years in the industry, I have never come across a sibling creative duo. All great creative partnerships are based on intuition and something close to telepathy. With the Stangl brothers this reaches new levels, resulting in brilliantly seamless work."
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