File For Tdiu While Working? in TDIU Unemployability Claims Posted December 9, 2008 Hey All, Actually title 38 part 4.16 speaks about marginal employment. "Marginal employment shall not be considered substantially gainful employment. For the purposes of this section,marginal employment generally shall be deemed to exist when a veteran's earned annual income does not exceed the amount established by the US Department of Commerce, Bureau of the Census, as the poverty threshold for one person". However I would never test this since the Va has been getting very rigid in awarding iu lately.