Mineral rights. Oil executives. Small business owners in local oil-rich economies -- or manufacturing entrepreneurs whose transportation costs have plummeted.

As oil prices have plummeted since last fall, many clients are finding that their circumstances have shifted, and that they need their advisor's help to navigate and understand a volatile market.

"We're spending a lot of time talking with clients, making sure that we not engaging in knee jerk reactions," says Jesse Clinton, a partner and managing director at Snowden Lane Partners and who has clients with mineral rights in Texas. "We're looking at what is our exposure to oil and maybe how we can take advantage of it."

In a recent research note, Credit Suisse analysts Jan Stuart and Johannes Van Der Tuin wrote that they thought the low point in prices had not arrived, "since fundamentals will likely not begin to improve until late this quarter." They lowered their oil price forecast tough for West Texas Intermediate crude to $44 per barrel in the first quarter; they also pushed back their estimate of when oil prices would rebound to $75 per barrel to mid-2016.

Of course, oil prices won't stay low forever. But while they are in the dumps, advisors should be mindful of the many ways their clients may be affected -- and act accordingly.

1. 'Mailbox money' will get squeezed

One group that will feel the pinch if prices continue to fall (or even plateau at current levels) is clients reliant on mineral rights for a portion of their income. Lower prices could lead to fewer wells being drilled as well as lower payments from producing wells -- what those in the industry call mailbox money or rental checks.

"The biggest change that you will see is in new production," explains Jonathan Meaney, an advisor with Carter Financial Management, an independent firm affiliated with Raymond James Financial Services. "With lower prices, the likelihood of new production -- new leases, when you are approached by a group that wants to drill on your land -- the likelihood of that has gone down."

Meaney, who is based in Dallas, says that some landowners may have already seen deals evaporate if they weren't finalized before the drop in prices. He adds that if prices stay low, then the sign-on bonus could be diminished for those who do get a deal inked.

"Anyone who owns minerals rights is concerned," he says.

In response, advisors whose clients who have substantial wealth based in minerals say they are reviewing financial plans and checking to see if a new normal requires rebalancing or other action.

"Sometimes people can get lulled into complacency," says Merrill Lynch broker David Nethery, who is based in Dallas. "I would reiterate [that] when their investments go down then it's time to take stock, to take someone's temperature and ask: Are we really as aggressive an investor as we thought we were? Now is a good time to do that."

Van Pearcy, an independent advisor with Raymond James Financial Services in Midland, Texas, says his team does cash flow analysis for their royalty owner clients.

"There is a depletion rate for royalty income. If you drill, it should diminish over time," says Pearcy, who adds that the rate can range from about 5% to 20%, depending on a variety of factors.

Pearcy, whose home base is in Texas' famed Permian Basin, says his office can do an analysis for each of their clients, looking at their goals and the current price of a barrel of oil.

"We can show them today: Are you going to have to cut your spending or maybe not fly your airplane as much as you have been? We just have to go through and look at it for each person," says Pearcy, who is based in Midland, Texas.

Fortunately, he says, his Texas clients have been through oil's boom-and-bust cycles before. "It's not their first rodeo. They know to expect this because we've seen it over and over. People who have lived out here for a long time know it. It's an easy conversation to have," says Pearcy.

2. Company stock may take a beating.

A lengthy period of depressed prices could also hurt those who work for or own energy companies, advisors say. Executives and other longtime workers could find themselves significantly overweight in a sector that may take a beating.

Local geography will play a key role in possible repercussions. Drilling activity could slow down noticeably in areas where the costs of such activity are high. Hiring freezes or layoffs could result.

"Geographically, you will see this hit some areas harder than others. If you are spread around and diversified, if you have a mix of natural gas and oil, then it may not affect you as much as someone who is all in the Bakken," says Paul Midkiff, head of oil, gas and mineral management services at Wells Fargo Private Bank.

For clients who are dependent on the industry for their livelihood, diversification is particularly important, says Jeanie Wyatt, CEO and CIO of South Texas Money Management in Houston.

"If a client comes in and a big part of their income is coming from oil or gas, then we advise them to diversify their liquid assets and it's exactly for this kind of scenario," says Wyatt, whose firm has five offices in Texas.

"We're doing a lot of outreach and communication, mainly just to make them feel more secure about where their accounts with us are positioned," says Wyatt, who says her firm has been defensive on energy stocks for about a year.

Rebalancing for clients who need it could mean moving assets into securities that benefit from sustained cheaper energy bills, say some advisors.

"One way we've benefited is that we have been overweighted in airlines," says Wyatt. "For the last year and a half we've been overweighted on airlines because of their fundamental value and the improving operating environment.This is a windfall [for them], quite frankly."

3. Small businesses may get squeezed.

The economic fallout could hit small business owners in oil-rich areas as well as those who provide ancillary services to the energy industry.

"Houston may be more diversified than it was in the past, but it's still very impacted by the energy industry," says Wyatt, who is based in the city.

For instance, pipelines connecting oil-producing areas with refineries and markets could see less activity if prices stay low long term, says Meaney. "If you have a field where production is likely to be cut, then you might see pipelines that are not full 24 hours a day," he says.

Meaney notes that a lot depends on how low prices go and how long they stay there: "In some places, where it's a little more expensive to drill, you'll definitely see less people on these projects."

4. There may be buying opportunities.

Not all of the ramifications are bad, of course. In Midland, Pearcy, who thinks the price drop is temporary, says some of his clients see this moment as an opportunity.

"In the last four weeks, we probably had anywhere from $5 million to $7 million of net new money coming in from oil and gas clients wanting to buy more stock in oil and gas companies," he says. "We had people saying this is a great buying opportunity, particularly for those companies that we feel are well suited to weather this volatility."

Pearcy, who says that he emphasizes diversification with clients, explains that psychology of the energy belt is different. "You got to remember that the environment of the people who work out here. Every time they go poke a hole in the ground, it's a huge risk. It's an all or nothing risk," he says.

He also says that these clients have a tendency to invest for the long-term because they are more comfortable with the industry.

Advisors also note that if prices stay low for the long term, there could be an uptick in M&A activity, as energy companies with healthy balance sheets buy those that are overleveraged.

5. Cost structures may change.

Meanwhile, small business owners may see some direct benefits as their expenses drop, says Edward DiConza, an RBC broker based in New York.

He is having conversations with some clients about how their firms might make use of those cost savings -- although he adds that the options available depend on a client's particular circumstances.

"It varies industry to industry, but you have people considering whether to ramp up hiring compared to previous years. Not dramatically, but better than in past years," he says. "This type of reduction [in energy costs] might allow them to get a pricier piece of talent than they might otherwise have afforded. Cash flows are improving for small business."

Farmers are likely to benefit from cheaper energy, points out RBC broker Mark Dewane: "Food growing and harvesting is very fuel dependent."

And many clients will simply benefit as they save more at the pump, advisors note. "The decline will almost immediately put money in the pocket of every American through lower gasoline prices," adds Dewane, who is based in Phoenix. "Billions will be saved as Americans fill up their tanks. On average, the annual savings could be about $700 per year, per driver. That is a lot to the average American."

That could help the U.S. economy more broadly. "These kinds of lower prices, who does it affect? It affects the consumer," Meaney says. He also says the drop in oil prices should benefit "anything consumer related, like shopping, retail, travel, dining and anybody who does any shipping -- 18-wheelers. Anything to do with the consumer should be pretty good this year, just because you've got more people with money in their pockets."

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