We look at joint regular variation properties of MA(∞) processes of the form X = (X k , k ∈ Z), where X k = ∑j=0 ∞ψj Z k-j and the sequence of random variables (Z i , i ∈ Z) are independent and identically distributed with regularly varying tails. We use the setup of M O -convergence and obtain hidden regular variation properties for X under summability conditions on the constant coefficients (ψj : j ≥ 0). Our approach emphasizes continuity properties of mappings and produces regular variation in sequence space.
