Question: How long do companies such as boots keep security camera footage for in the u.k? 

Answer: Newer, larger and faster computers means some companies now record the security cameras right to their computer's hard drive. Or use burnable DVD recorders. If this is the case those records could last years. They could store a year's worth of DVDs in 2 3" binders on a shelf. Who knows how long a store might keep records these days if they really wanted to.
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