In addition to her shorter piece on the English Levellers, Roberta Modugno has provided this longer, footnoted piece as well, including:
The Levellers were concerned with economic rights and these economic rights were a direct consequence of the right to self-ownership and included individual property rights, freedom to produce, sell, buy and trade, and to do all this without license, monopolies, regulations and arbitrary taxation. That is to say, they advocated a free market economy.
The right to trade freely was considered a natural right by Lilburne, or a “native liberty” as in Overton’s Remonstrance. Arguing from the theoretical supremacy of natural rights, Lilburne rejects any form of regulation of trade. The right to free trade is a birth right: a legal fundamental liberty.