Halliburton (HAL) shares are under pressure and implied volatility is ripping higher on reports the “company knew BP cement well was unstable” — Marketwatch. Shares are off $3.15 to $31.27 and options volume surged on the news. 130K puts and 67K calls traded in the oil driller. Recent trades include an April 20 – 28 (2X1) put ratio spread, bought at 92.5 cents, 1250X. Front-month puts are seeing heavy trading as well. November 30 puts traded 17,370x. Another 11,000 November 31 puts changed hands. Players are scrambling to buy premium on concerns about additional downside and implied volatility is rallying 49 percent higher to three-month highs of 49.