No, you can't claim that. This is not sporadic activity. He is required to file Schedule C for this income. He may want to talk to his employer to find out the reasoning for this type of reporting. He can do the following, but I'm sure there would be some repercussions from his company.
Form SS-8
If it is still unclear whether a worker is an employee or an independent contractor after reviewing the three categories of evidence, then Form SS-8, Determination of Worker Status for Purposes of Federal Employment Taxes and Income Tax Wi... PDF, can be filed with the IRS. The form may be filed by either the business or the worker. The IRS will review the facts and circumstances and officially determine the worker’s status.
Be aware that it can take at least six months to get a determination. A business that continually hires the same types of workers to perform particular services may want to consider filing the Form SS-8 PDF
Misclassified Workers Can File Social Security Tax Form
Workers who believe they have been improperly classified as independent contractors by an employer can use Form 8919, Uncollected Social Security and Medicare Tax on Wages, PDF to figure and report the employee’s share of uncollected Social Security and Medicare taxes due on their compensation.
