Adding the essential background related to the sentence, Marathon has made an estimation of the value of its remaining stake in Protalix, indicating the ongoing evaluation of its investments and financial positions in the market.

Weaving in the sentiment highlight, the estimation of the remaining stake in Protalix at $27 million reflects a neutral sentiment, showcasing a stable and consistent assessment of the company's financial standing.

Synthesizing the enhanced sentence, Marathon calculated the value of its remaining stake in Protalix at $27 million, signifying the continued evaluation of its investments and delivering a neutral outlook on the financial positioning.