LONDON -- There are thousands of companies listed on the London Stock Exchange. At any one time, I deem that only a few are worth owning. Here is the lowdown on three of the shares in my portfolio today.

1. Lloyds Banking Group
Although shares in Lloyds Banking Group (LLOY 1.15%) (LYG 0.80%) have fallen heavily in recent days, they have still managed a 7.1% rise so far in 2013. In 2012, Lloyds shares rose 83.8% -- more than any other company in the FTSE 100.

I first bought the shares before the eurozone crisis blew up. I had decided that if the company did not need to raise more capital, then the shares were cheap. I paid an average price of 43.1 pence per share. Today, Lloyds shares cost 51.5 pence.

Recent results from the bank confirmed a 42% reduction in impairments. I expect these costs to fall further as the U.K. economy recovers.

2. SOCO International
SOCO International (SIA 0.09%) is an oil and gas exploration and production company. The company produces an average of 55,000 barrels of oil per day from the TGT oilfield offshore Vietnam. In addition to this producing asset, the company has significant exploration opportunities in Africa.

Historically, SOCO has not been the kind of company to hold on to producing assets. I believe that an international oil major would place more value on SOCO's Vietnamese operations than the stock market does today.

SOCO is currently engaged in an assessment process that could see the company report a significant upgrade in reserves by the end of 2013. I will keep the shares that I bought for less than 300 pence.

3. Vodafone
I bought shares in Vodafone (VOD -0.15%) (VOD) for 160 pence in the middle of last November. Since then, I have received an interim dividend of 3.27 pence per share. Today, the shares can be sold for 168 pence. I am comfortably in profit on my investment.

Vodafone has increased its dividend to shareholders every year since 1998. Expectations are for another dividend increase for 2014.

The value of Vodafone's stake in U.S. mobile operator Verizon Wireless becomes clearer with each dividend Vodafone receives on its investment in the company. Vodafone is currently using this dividend for a 1.5 billion pound buyback of its own shares.

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